Well, it all depends on how many times you have taken your car apart.
I did my entire 93' four door blazer with a dynamat type sound deadener, I also used 3M rubberized undercoating inside the doors and well, under it. I knew that car like the back of my hand. Ive only done about a quarter of the typhoon. I found that one of the hardest areas to dynomat were the kickpanels. It was kind of hard to find just the right amount to use, without bulging out the panels. The best thing to remember is that you need to remove ALL of the factory sound insulation, it will be mofo, especially the adhesive they used to glue it down, definitly invest in some adhesive remover (3M). I should add that I have never done a headliner in a car, it could be a pain to get it to look right with insulation under it.
Good Luck,
RJ