There are a lot of "tricks" that people use to get someone dry, but the key to being super dry is to go into prep wk, already dry enough that you don't need to make changes that are too dramatic to begin with. Ideally, someone goes into prep wk not needing to do anything dramatic. The less you have to do, the better the chance is that things will work out well. The more you mess with water, sodium and diuretics, the bigger the chance is that the result will fail. 

So there is no a be all, end all approach that will work bes for everyone. I'm afraid to even give a general water cutting plan out here because I could see it really back firing if the wrong person used it. 

So once again, my advice is to look good before you cut water and make as few changes as you need to to get them crisp