One of my favorite solo techniques
I've been an avid crossdresser for years. I also like to play around once I get dressed up. I will often put a little lube into an unrolled condom and slip it over my erection before getting dressed. My dressing often involves multiple layers of panties, hose and a girdle followed by a slip of some sort.
I discovered that if I dress up then lay across the bed, I can rub against a pillow and cum in no time at all. It also leaves everything neat and tidy while keeping my undies clean. One variiation involves the lubed condom under some plastic panties and a half slip so I can sit and surf the net while I play.