Quinn tips

A good combo Quinn can use to trade is to wait for a target to be marked, then Auto Attack them for the extra damage, immediately after, you can Vault (E) into the same target to apply the small CC and mark the target a second time, immediately landing a second charged AA, be careful as to where you land and keep a mental image of where you are going to land, depending on the support or marksman, it can get you into awkward positions.

W It's active is meant to be used to avoid dangerous face checking, reveal places over walls or to keep vision on a potential kill, so you will want to save it for a moment where you can't ward a brush you need to check, I.E. You fear the enemy jungler is sitting nearby in a brush and want to make sure before doing anything else or you are chasing down a potential kill that's getting out of sight, like getting into brushes or leaping over a wall, it's always a good tool when you want to check for important objectives, like Dragon or Baron, and it will give your team good intelligence before teamfights.

R it slightly changes the way your basic attacks work as well as giving you a AoE burst damage as finisher move by triggering R a second time or when it's time runs out, basically, it will double your passive Attack speed boost while giving you some chase and burst potential while also giving you a nice movement speed bonus that decays over time, at the expense of becoming a melee champion for the duration of it's effect. Use R when hunting down a player with low enough health to guarantee your burst will kill them quickly, since you have a nice speed boost you can chase down players that are relatively far away, maybe you missed out a teamfight and the enemy has a champ or two there with low health, be the janitor hero and use your ult to quickly get to them and Vault in for some very hard to dodge burst AoE. or Use R to make sure you will survive if the fight doesn't go your way, Vaulting as Valor won't bounce you back so you can use your W to spot a jungle camp and Vault to them to gain distance, and your speed boost can rarely be matched by any other champion, even if they ghost, your initial NO2 will give you the advantage, Don't use too much R or your Valor may explode.

Do NOT initiate a duel as Valor unless it's pretty obvious you will win the trade, otherwise you waste your passive and chase potential for an arguably limited AS boost and some extra burst in the end, your blind does not last long and it can barely guarantee you will only dodge one hit with it.

Hope that helps out.