I don't secrete any pre-cum at all. How can I get my body to secrete it? I find it very sexy when my partners do. Why can't i?

Everyone is differen. Depending on your own biologic make-up, sexual arousal and stimulation and locus of control, one may or may not secrete "pre-cum". This is a fluid made by the cowper's glands in the distal penis. It is most likely secreted for lubrication. It is a clear thin liquid as opposed to a thick opaque fluid like semen. This may just be you and nothing more. Try more arousal and stimulaltion.