I'm not much of a pro but i'm decent as a LoL player I chose flash and Ignite early game mainly because of the littlest of damage that it does to prevent an enemy from surviving early game. This helps a lot for Quinn, as the ignite may kill some opponents and help you get that extra little bit of gold. Whereas when using cleanse instead of ignite, i don't really find use of cleanse early game as most of the time u can just avoid being contacted by the enemy skills but cleanse can stil be of an option for those playing adc's its a useful summoner spell as well as barrier.

Max your Vault(E) first, as it give less CD each level and it marks an enemy whenever casted upon, every time an enemy gets close enough and when i'm not in danger I always use my Vault to harras the opponent as it slows them and the next step, all you need to do is attack them once while the mark is upon the enemy. I keep Blinding Assault(Q) at level 1 until end game because it's blind is still at 1.5 sec's regardless the levels and it's damage output isn't as effective as Vault(E) either, therefore I use spare skill points to add to Heightened senses(W) due to the attack speed boost passive.

Quinn is a quick Mobile character but she can only chase and when getting chased please do not try to kite with Quinn as she is still glitchy in that matter, when your a pro Kog Maw player and you can kite really well just dont incorporate kiting in Quinn's style as it doesn't suit her. Just only try harrasing whilst running away when you have your vault active meaning when its up.