Keep your farm above 7cs per minute.
Go to U.GG and look at the Pro Builds tab to see what runes you should be using and what abilities you need to prioritize. (It's Q, E, W btw.)
Find a good, in-depth guide about combo's and gameplay tips for Zed either no this site or YouTube, or both.
Play a ton of PVP games. Norms, Ranked, whatever.
Do CS drills.
Research different common Zed matchups.
Research lane control, lane dominance, and lane priority.
Research when to roam and when not to roam.
Find a high level Zed main or Zed 1 trick on twitch and watch their stream and stream highlights whenever you aren't in game.

It depends on how much you was impact full in the game, usually the best way to get S or S+ is keep your farm high and die less. But i think you should just try keep be better and try to learn the game, S and S+ will come, and they will continue to come even after you done with the mastery level.

become Faker

watch llstylish and style it up