Most Helpful Girl
Eye contact is a perfect way to let a girl know you like her without saying so. Look her in the eyes, don't shy away and don't check her out below the neck at this particular time.
If she meets your eyes, smiles back or blushes, then you may have a chance. If she frowns or gives you that "what the heck?" look, back off for a while.
Most Helpful Guy
Offer a massage, give her a hug, if she asks for help then concede otherwise you ask her for help and put your arm over her. Those are the most obvious signs that you like her and she'll probably get you message and remember you're going to be putting yourself in a position to get rejected. You can be less suggestive though and flirt on a lower level with eye contact/staring laughing randomly when she looks at you, etc.0