Now how can i install optifine?I tried putting the jar in the mods but it doesn't work.
And btw, what version of minecraft do i have to use? 1.7.10 or 1.8.8?
EDIT: I have another problem.When i try to connect to servers, i get the "Failed to login:Invalid session (Try restarting your game)".Does sb know how can i fix this?