http://reranchstore.stores.yahoo.net/fencuscol.html

I need help understanding the painting and finishing process. Here is what I understand so far.
1)Help make the Ash wood grain pop: I have heard different ways to make this happen and I would love to hear what you have used before
2) Paint in multiple thin coats. I know it's important to keep coats thin to avoid messy runs. I need help understanding wet and dry sanding. What's the difference? How much is necessary.
3) Nitro Finish. How much do I put on? Is it more personal preference? Will I need to sand the finish as well? I assume I would if too much finish in one area. Can I give the guitar a more vintage look if I use more nitro?
I am basically a guitar painting noob so please shower your paint and finishing wisdom upon me. I know I will make some mistakes, but I would love any help you can offer.