That's a common question on this site. There are a few things you'll need to consider. The first in my opinion is whether you want to go with single coil or humbucker pickups. Single coils are brighter and thinner sounding (think Hendrix, David Gilmour, yngwie). Humbuckers will offer a fatter sound with more low end, more output (think heavy metal and hard rock).

The next thing to do is try some guitars out. Go with what is comfortable for you. Decide if you want a stop tail or a whammy bar. Stop tail guitars have better sustain, but whammy bars are so much fun.