To cover a model using 50/50 clear dope and thinner . You just coat the areas where you what to attach your tissue. About three coats will do, your wood will have a shining apearance. Lightly sand your wood after each coat. Then when its time to cover, cut out a piece of tissue to cover the section of frame your working on. To attach your tissue, lay your cut out piece on the section of frame, then take a Q-tip and dip it in dope thinner and run it along the edge of your tissue. The tissue will be attached to the frame in about 15 seconds, the time it takes for the thinner to dry.
After all your sections are covered you can shrink your tissue by spraying it with water or rubbing alcohol. Make sure you pin down your wings and tall surfaces, to keep them from warping. After assembling your model , paint your model with one to two coats of 50/50 clear dope and thinner. This will seal and toughen up your tissue.
This method is called dry covering, this is my favorite way to cover a flying rubber powered airplane.