I'm afraid the only way to avoid dust may be that effort of leaving the shop out of commission, or use something that dries faster. As for the T shirts, you can buy them at second hand stores…or you can use those blue paper shop towels that any auto store or Walmart stocks. These blue ones (called Shop Towels) are lint free and are great for wiping varnish, use and toss. It does pay to wear those disposal nitrile gloves. I typically finish after assembly, though there are arguments for both ways. I wouldn't "default" to either, but pick the one that would seem to work best for a particular project. Some of them would be almost impossible to finish after assembly, and visa versa. I don't flood any finish on, though I will do that with dyes. Especially on red oak, it will expel some of that at a later point. It common to recommend a book, and i will: Bob Flexner's book excellent and easy to read. There is another one by Jeff Jewitt has pretty much the same info, but is organized a little different. One or both should be required for any hobby shop.