I installed the cabinet, counter, sink and faucet before building the drawers, so that i knew how much space the plumbing would take up. The drawers are U-shaped to maximize storage while staying clear of the plumbing.
The drawer bottoms are built of the same 3/4" good on 2 sides plywood, leftover from the 4' x 8' foot sheet, that the cabinet was made of. And i used 1/2' mdf to build the drawer sides, fronts and backs. The key here is making sure you have accurate measurements and precise cuts:
Then i simply glued and brad nailed the pieces together:
Prime and paint the drawer and voila. This is the first of two drawers:
Next the drawers are installed into the cabinets using drawer glides that you can buy from any big box.
NOTE: For the Richelieu drawer glides that i used, the drawers should be 1" narrower then the face frame opening, as the glides require 1/2" of clearance on either side. I also had to build out where the glides where attached until it was flush with the face frame.