Get a good pair of needle nose pliers, jewelers screwdrivers, and wire cutters. Heavy drapes over windows will keep outdoor noises from ruining your tracks. Also, tell the neighbors to keep it down after 3am, you're trying to make music in here. Every time you burn a CD don't forget to write down what's on it on the cd itself. You will thank me 10 years from now when you have thousands of songs.
Access is everything.
When laying out your studio, route all the AC cords first. Put them in a pathway that will cross audio cables at a 90 degree angle. I say no, though clearly your studio will look neater if you do. At a normal listening level, with nothing playing, gates switched off, your audio should be silent. This helps during the mix as you can make better decisions about boosting a single level or cutting everything else to make an instrument cut the mix.