When i playing melee champs or any champ in general i get to low or get to much out of mana and back after i get 10cs then after 10 or so more cs when i come back i have to back again how can i stay healthy in lane and do trades?
Stop relying on your skills to farm CS. Go into custom matches with some champs you want to use and learn how to farm without using skills.
After that, try and take what you just practiced into Normal games against Human Opponents.
You should be using your mana/life to trade/harass your opponent when it's necessary. Learn to conserve it for when you need it and your CS will improve greatly.
Watch this video for even more tips and strategies. His accent is a little annoying at times, but it is very helpful.
try easy to farm champ like tryndamere who can not last hit but has to push and dominate
