How upfront should you be when you hit on a girl?

How do you avoid the trap you set yourself in allowing her to think you're a nice guy because you are trying to be civil about hitting on her (yes i'd love to be overtly aggressive with my pick up but at the risk of being labeled as harassment, I have to be smarter than to do so)

Yes having present social validation might help but you don't always have it, so how do you give that tingle while still giving plausible deniability..?

Only thing I have locked down as a tip myself is that so long as you don't use "trigger words" (not the way their are used mainstream but just words that are simply explicit that whatever format you use them they'll have a strong annotation of pervertedness/sexual nature) your message sounds more approachable. Example avoiding words like sex, fuck, pussy, and using relative words that hold more expressive use than just being sexual.