I want to have an affair with my coworker

So, I’m in major lust with my coworker. He is married and he appears to be happy. I feel this amazing chemistry with him, however, I don’t know if he feels that for me. So far the only thing that happens is he communicates with me slightly outside of a professional manner, via text. He does not do anything super unprofessional, he just communicates with me in a manner no other coworker would. For example, at my work no coworkers would share jokes via text. It is 100% professional. I just want to have a once in a life steamy affair with a hot coworker. I’m ok making the first move, but I’m unsure what I should do to get things going. I don’t want to cause any damage to his marriage. He is a high-powered, highly compensated employee so I know he would never make the first move and risk his career. I just want a fun steamy affair. Men, what should I do to get things going?