John.
I use Dorlands wax as my medium. I use it at a ratio of 50/50 or more. It dries in a week at most. However, the wax makes the oil finish matte. I like that as there is no glare. I paint alla prima so I don't need to worry about fat over lean and crap like that. To work oils it is thick paint over thin paint. You can scrape out a passage should you not like one and then go back in and repaint it. I don't varnish as I don't need to. The wax is a protector and the finish is the same all over. Less wax more sheen but also more drying time. I do not use any solvents. It's all about touch and leaving it alone. The trick is don't mess around. Make your strokes deliberate and let them be. You can mix on the canvas. You can pick up three similar values at once and let the stroke marry the colours. It's down right fun when it works. Hope this helps. If you have a question, ask.