Your best bet is to first, study the growlog forum. There's shitloads of opinions on this site, but the best opinions come with instructions and pictures. (a grow log)
Find a grow similar to yours, and see what they did. Any questions after that, give a holler.

The best techniques I've ever seen to get better quality and larger quantity, are knowledge and patience.

Also, 1000w in a closet is going to be pretty tricky. Heat will definatelly be an issue. Just because the spread pattern of a 1000w is approx 4' x 5' or whatever the ad says, this does not really mean it's a good idea to limit the size of the growspace to that dimension. The more cubic feet of growroom airspace, the better.
Rusty Trichome Reviewed by Rusty Trichome on . New Closet Grow I'm in the process of building a new grow cab in an unused closet with dimensions H- ~5', W- 4', D- 3'. I've built a 3' space beneath the "floor" of my cab for a reservoir as I'm retooling my hydro system to turn it into a ~20-30 plant aero cab. I've already got a 1000w HPS I'll be moving in to the new cab as well with a cooltube and 6" ducting/inline fan to vent the lighting and an 8" duct fan exhausting hot air out the top of the cab and passively pulling cool air in through the "floor." Rating: 5