My boyfriend gets turned on by temptation and teasing.
I let my lips brush his when i speak to him really close but if he tries to kiss me i pull away enough so our lips still brush each other but not so we are kissing.
Also i brush my cheek against his, linger my lips across his jawline and corner of his lips and i breathe into his ear gently that it sends shivers through his body. It makes him go crazy and passionate. XD