Don’t Stare
So you’ve spotted a girl and you want to go for it.  Here’s your next tip: Don’t stare.  Your goal is to convince her that a connection between the two of you has happened by a glance and that the glance occurred when both of your eyes met for the first time.  Obviously you’ll need to time that moment well, but you don’t want her to think you are or have been staring at her.  Be subtle with how you watch for the moment when you can create the ‘instant connection.’  The trick is to look at her with your peripheral vision, look away the moment you notice she is about to look in your direction, and then to look back almost immediately and then lock your eyes on hers to create the ‘I just noticed you’ moment.
Show your interest, then look away.

Once you create the ‘I just noticed you’ moment, fixate on her eyes for a second or two longer than would normally occur as a glance, just enough to let her know you’re interested.  Then look away immediately.  Again, you don’t want her to think you’re a creep, and if she thinks you are staring, it will do exactly that by making her feel uncomfortable.