Jan,
I've waxed chains for a while. My preference, (more subjective, as opposed to something I have data for) is to clean a chain with mineral spirits, dry it out overnight, soak it in a light oil such as Marvel Mystery Oil, let it drip dry, then pop it into a molten paraffin/oil blend (usually a commercially available concotion such as Chain Wax). Let it sit in the hot wax for about five minutes, then carefully remove. Let cool for several hours on clean newpaper or brown paper sack. Run it through your fingers a couple of times when cool to remove much of the wax that will flake off. Install and ride. I wax chains on bikes that I ride infrequently. My "daily" riders get oil once a week, or more often.
A friend was with my wife several years back when she flatted. (Classic content, she was on an '83 Bianchi, Campagnolo equipped of course.) Being gallant, Caroll insisted on changing the flat (rear naturally) for her. Later at the coffee shop he noted that he'd never handled such a clean chain and wanted to know how I did it. In fairness, he was using a brand new product "White Lightning" which was a black mess after a Saturday morning thrashing.
Sid Smith In Lake Forest, IL where I rode up Courchevel last night with Lance and Marco at the 2000 Tour. Man I love those tapes!