[header] How to stop staring at a girl's boobs [title] Focus on making eye contact. [step] Not only will making eye contact keep your eyes off of a girl's chest, it's also a sign that you're confident and engaged. To keep your eyes focused on hers, try noticing the color of her eyes or what shape they are. 
If you're having trouble maintaining eye contact, try looking at the space in between her eyes instead. [substeps] Remember to look away every so often.