Starting the situation off by playing games (giving attention then blowing them off) gives mixed signals and its probably never a good idea if you're interested in more than just sex. If you're in to the chick then be into her. Don't shower them with tons of attention right out the gate or they'll always expect that. Don't say or do anything you don't mean. They keep track of that shit. Keep things light and casual at first, no one is telling you to marry the girl tomorrow or anything. Approach each situation as you'd like to be approached.