Most of my experience from eggwars comes from Bedrock, but most of the stuff I talk about should apply to Java edition as well. I also play mostly solo but have experience in duos and teams of 4 as well. I hope this helps you guys out and you can as least learn one or two things that can help you out.
1) Win the Diamond Generators = Win the Game
Obviously, the diamond generators are important. By taking the diamond generators at the middle islands, you are putting your opponents at a severe disadvantage. As long as you are mediocre at PvP, you will almost always beat someone in leather armor if you have iron armor and a diamond sword if it's a straight-up 1 vs 1.
2) When rushing, kill the player before going for the egg
If you're trying to take out someone on their island while their egg is still up, go for the player first. I've been rushed so many times in situations where they go for my egg first and they end up failing. Even when they break my egg, it's usually an easy kill because I have a couple of hits on them. When rushing, go for the player first. While the respawn timer is going, you should have enough time to break their egg. 9 times out of ten, they'll start punching you, and you can get a final kill in only a few hits.
3) If you get rushed and you die and your egg is broken, run.
Let's say you're on the opposite end of the rush mentioned in number 2. You have nothing, you're egg is broken, and there's a player next to you fully kitted out. You have no chance of taking on someone that killed you and broke your egg, so you need to just get out and find another island to get on. The 10 second grace period for when you spawn if should be enough time to get out, so use it to your advantage.
4) Learn to speed bridge.
Bridging is a vital aspect of egg wars, as it's the only way to go from island to island (except ender pearls). Taking 15-20 seconds to bridge out by crouching puts you at a huge disadvantage against someone that can get to the main island in only 2-3 seconds. It's not difficult to do, and there are hundreds of tutorials on youtube. Speed bridging also makes it easier to rush, as it gives the person you're going for less time to react and get gear. Overall, it's just a good skill to have in a game like this.
5) The Up-And-Over rush technique
If you're trying to take someone's egg, sometimes your opponent will camp their bridge to try and knock you off. Although there's a decent chance you can make it across, you shouldn't risk it. Instead, use the Up-And-Over technique. All you need is some blocks. First, build a tall column under you near the base of their bridge, at least 7-8 blocks tall. Make sure you watch out for people, as they might try and hit you off. Next, speed bridge to their base and jump down and do the job. You can almost always get to the person's island doing this, and it's very hard to counter.
6) The void is your best friend
You can have prot 4 diamond gear or no gear, but you will never survive a fall into the void. Often times when fighting, especially someone with equal or better gear than you, you should be always trying to hit them off the edge. I really only see people try to do this on bridges, but it works for just about every area except maps with a larger middle island. This works especially well on overpowered, as you don't really take damage once you get enough armor.
7) Don't underestimate golden apples
This may sound obvious, but it's crazy the number of people I see while playing that don't utilize one of the best items in the game. Golden apples make you go from being somewhat hard to kill with straight-up damage, to being impossible to kill with damage. You can even eat them while getting hit and still benefit, as long as you aren't close to the edge. Nearly all gold you get should be going towards buying them.
8) "Bum Rushing" won't win you games
This applies a lot more to solo, as it can work as long as you have good teammates in squads, and maybe duos if you're confident. Bum Rushing is when you rush an opponent's island with just a pickaxe or really weak gear. Although the success rate of breaking their egg is somewhat high, it really doesn't do you any good. You will most likely die in the process, and all it will leave you with is no gear, and someone really angry at you and will most likely go after you.
9) Use chests
Once you have full iron and a diamond sword, you should be putting your extra diamonds in a chest at your base. If you die, it's much easier to recover if you have diamonds in the chest. This can also catch the person who killed you off guard if they try to rush you immediately after killing you, and you have full iron again. I'd also put excess gold and iron in here too.
10) Watch your neighbors
I'm not sure how the maps are on java, but a majority of solo maps on bedrock consist of 3 player islands around a small island that connects to mid. It's a very good idea to go-to mid, but you need to keep an eye on the people around your island. If they aren't bridging out, cool. But if they do bridge out, stay close to your egg and do everything you can to break theirs. If you get the two people near your island eliminated, you can stay in mid as long as you like without having to worry about a surprise attack.
If this does well I'll probably write another one.
Edit: The title typo is really bothering me
1) Win the Diamond Generators = Win the Game
Obviously, the diamond generators are important. By taking the diamond generators at the middle islands, you are putting your opponents at a severe disadvantage. As long as you are mediocre at PvP, you will almost always beat someone in leather armor if you have iron armor and a diamond sword if it's a straight-up 1 vs 1.
2) When rushing, kill the player before going for the egg
If you're trying to take out someone on their island while their egg is still up, go for the player first. I've been rushed so many times in situations where they go for my egg first and they end up failing. Even when they break my egg, it's usually an easy kill because I have a couple of hits on them. When rushing, go for the player first. While the respawn timer is going, you should have enough time to break their egg. 9 times out of ten, they'll start punching you, and you can get a final kill in only a few hits.
3) If you get rushed and you die and your egg is broken, run.
Let's say you're on the opposite end of the rush mentioned in number 2. You have nothing, you're egg is broken, and there's a player next to you fully kitted out. You have no chance of taking on someone that killed you and broke your egg, so you need to just get out and find another island to get on. The 10 second grace period for when you spawn if should be enough time to get out, so use it to your advantage.
4) Learn to speed bridge.
Bridging is a vital aspect of egg wars, as it's the only way to go from island to island (except ender pearls). Taking 15-20 seconds to bridge out by crouching puts you at a huge disadvantage against someone that can get to the main island in only 2-3 seconds. It's not difficult to do, and there are hundreds of tutorials on youtube. Speed bridging also makes it easier to rush, as it gives the person you're going for less time to react and get gear. Overall, it's just a good skill to have in a game like this.
5) The Up-And-Over rush technique
If you're trying to take someone's egg, sometimes your opponent will camp their bridge to try and knock you off. Although there's a decent chance you can make it across, you shouldn't risk it. Instead, use the Up-And-Over technique. All you need is some blocks. First, build a tall column under you near the base of their bridge, at least 7-8 blocks tall. Make sure you watch out for people, as they might try and hit you off. Next, speed bridge to their base and jump down and do the job. You can almost always get to the person's island doing this, and it's very hard to counter.
6) The void is your best friend
You can have prot 4 diamond gear or no gear, but you will never survive a fall into the void. Often times when fighting, especially someone with equal or better gear than you, you should be always trying to hit them off the edge. I really only see people try to do this on bridges, but it works for just about every area except maps with a larger middle island. This works especially well on overpowered, as you don't really take damage once you get enough armor.
7) Don't underestimate golden apples
This may sound obvious, but it's crazy the number of people I see while playing that don't utilize one of the best items in the game. Golden apples make you go from being somewhat hard to kill with straight-up damage, to being impossible to kill with damage. You can even eat them while getting hit and still benefit, as long as you aren't close to the edge. Nearly all gold you get should be going towards buying them.
8) "Bum Rushing" won't win you games
This applies a lot more to solo, as it can work as long as you have good teammates in squads, and maybe duos if you're confident. Bum Rushing is when you rush an opponent's island with just a pickaxe or really weak gear. Although the success rate of breaking their egg is somewhat high, it really doesn't do you any good. You will most likely die in the process, and all it will leave you with is no gear, and someone really angry at you and will most likely go after you.
9) Use chests
Once you have full iron and a diamond sword, you should be putting your extra diamonds in a chest at your base. If you die, it's much easier to recover if you have diamonds in the chest. This can also catch the person who killed you off guard if they try to rush you immediately after killing you, and you have full iron again. I'd also put excess gold and iron in here too.
10) Watch your neighbors
I'm not sure how the maps are on java, but a majority of solo maps on bedrock consist of 3 player islands around a small island that connects to mid. It's a very good idea to go-to mid, but you need to keep an eye on the people around your island. If they aren't bridging out, cool. But if they do bridge out, stay close to your egg and do everything you can to break theirs. If you get the two people near your island eliminated, you can stay in mid as long as you like without having to worry about a surprise attack.
If this does well I'll probably write another one.
Edit: The title typo is really bothering me
