[header] How to make a guy think about you [title] Make eye contact. [step] Locking eyes can cause crazy sparks. Don't try to stare deep into his soul (that could come off as creepy), but if you can catch his eye from across the room or hold his gaze while talking, you can have a major affect on him. 
Eye contact causes arousal and can lead to feelings of attraction. [substeps] Try catching his gaze and smiling as you look away.