Not really a technique, but a clean up tip. Tissue sucks. Use a paper towel. One to get most of the goo, one for final cleanup.
Also, to keep my jiz from filling up my belly button, when I feel I'm about to cum, I put a paper towel over my belly to catch the bulk of it. This is all the one I use to get most off the goo off my hands and dick.
Hell, I keep a roll of paper towels right by my PC.