What turns on a girl?

I usually visit my crush everyweek for a short period of time and She thinks I'm hot and a she looks at me the way she would when she likes a guy but we are really close and she will never admit her feelings to me. She doesn't have much time to spend with me so I just visit her before she goes to work. Lol it's hard being friends with a girl that you think is extremely sexy and beautiful when she walks around in a tanktop showing alot of cleavage and some tight shorts, with wild and exotic wavy hair even though she is attracted to you. So even though we spend time hanging out at her house I want make her feel comfortable around me but I don't want to go to far if I decide to become too affectionate and make her feel uncomfortable. She let's me kiss her on the cheek and hug her but thats the closest Iv gone without going too far. She thinks I'm a sweet and nice guy but she talks to me about alot of dirty minded stuff and if I say something dirty minded about her I get a awkward silence or if I texted her a dirty minded comment she would put "...ok". Is there something I could do or say that could get her turned on by me a little?