Winning or going even in lane is not enough, you need to take the advantage you have gotten for yourself from mid lane and use that advantage to apply pressure to ether top/bot lane (mainly bot lane unless you know getting the top laner snowballing is a good idea based on the champion they are playing).
Planning Ganks
Always check the lanes you want to gank situation,
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How much hp/mana does my teammates have then do the same for the enemy (just HP for enemy)
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Did the enemy already used summoners (most people ping them when they see the enemy used it in chat) and does the enemy have a ult ready to use? It's important to know so you won't get surprised while the gank is happening and will be prepared for it.
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Where is the minion wave positioned Example: the top lane minion wave is on my side of the map, so if i were to gank that lane it has a higher chance of getting a kill or blowing enemy top laner flash because he is farther from the safety of his tower
Another Example: is your team minions under enemy tower, they are so close to their tower that it's not worth ganking unless they are low enough hp wise for you to get a clean tower dive off easily without giving them kills back.
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How many minions are there? (if there is 2 waves of minions it's best to not gank that lane if it's early game)
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How well are both sides of that lane are doing? if your teammate is already losing to that lane badly then NEVER gank it, if it's bot lane losing bad gank top lane instead, top lane losing bad? gank bot lane instead, never ever gank a feeding lane.
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Where did you last spotted the enemy jungle and how long ago was that? If you last saw the enemy jungle top lane 5 seconds ago then that means you don't have to worry about enemy jungle counter ganking your bot lane gank assuming you're going for it right after you saw him.
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And last what champions are they playing? Because some champions are just not worth ganking at all if they make it really hard for a gank to actually work.
Roaming
.Always shove your minions into the enemy tower before roaming so the enemy mid laner will be forced to counter push instead of following your roams or else they will miss out on minion xp/gold.
.Typically whoever is closer to being under their tower is always going to be the person that reacts to skirmishes happening in the jungle/river last because the person shoving faster will have lane priority and if they try to help they would lose xp/gold which is huge for the early game (not that you should always be shoving because doing so opens you up to jungle ganks more easily and enemy solo laner if they have the tools to chase you, so unless you're mobile, strong enough to 1v2, or have your own jungler near by, try not to shove unless you're planning to roam)
.If the enemy mid laner is going to roam then quickly shove your minions into the enemy tower and get damage on that tower in situations where you know it's too late to try to follow the enemy mid laner or too dangerous.
Example 1: A enemy zed managed to shove you in and has disappeared into the river fog of war, he could be heading bot/top lane or he could be sitting there waiting to ambush you, so the best thing you can do is to not follow him and counter push the wave since you don't have vision of him, do not overextend to damage his tower till you have vision of him doing something.
Example 2: A champion like twisted fate, you will never reach to the lane he is planning to gank before has already made an impact so your only choice is to counter push hard and get tower damage onto the mid tower. If you see anyone that's not TF half way down the river to their intended lane to gank then it's already too late.
Mid tower is the most important tower in the game for map pressure since it opens up both sides of the enemy jungle and with it being dead they lost tower vision and their minions will be further back to their side of the map, try not to give your own mid tower for free.
Also when bot lane takes bot tower one of the solo laners need to take control of bot lane while the adc and support goto their lane so they can work on getting the next tower.
Get control wards and ward more often, work on your shotcalling game because someone on your team needs to be shotcalling so you all don't run around like headless chickens.
Don't play support and if you have to cause auto fill play a ap carry support since you can't trust your teammates (you can stop playing ap supports at plat elo since they will have more brains there)
I can't think of any other general tips to help you, hope this wasn't painful to read and if it was you'll find someone better at teaching people how to play than me anyways.
Good luck with the rest of this season.
