Not sure if you’re flirting or harassing? Ask yourself if you’d be talking the same way if the woman were in a position of authority. If she were a police officer, who you knew had a gun and a badge, and happened to be off duty, at a bar, or a convention… You’re free to flirt, since she’s not working, but if you cross the line into harassment, she could physically stop you, even arrest you. How do you tell her that you find her attractive?
With your words, not your hands. You introduce yourself. You talk. You tell her you find her attractive. You wait for her response, and if it goes further, you ask for permission to touch her. Simple. Now the same thing with every other woman.
And if you’re not sure she’s available, and you’re a little shy, you can ask one of her friends. Do not say, “Hey, can I hit that?” as if she’s a receptacle for your penis that no one else happens to be using at the time. Say, “Do you know if X is seeing anyone? I like her and I’d like to ask her to spend time with me, but I don’t want her to feel pressured if she’s not available.” You know. Like’s she’s a person.