The Redress Design Award shares a load of tips on zero-waste design online:

A useful PDF with hands-on tips and several examples.
Online videos:

• The Redress Design Award 2013 - zero-waste
• The Redress Design Award - zero-waste tutorial by Timo Rissanen. Here are his tips to master the technique:
  • Start from a pattern rather than from a design: you can work with sketches and patterns, but not finalize a design on paper. It’s important to start from the act of cutting the fabric, and not purely from the design.
  • Drape: you can also drape your piece of textile on a mannequin and start from there to work out the pattern. It can be equally helpful to try and fold your paper while drawing.
  • Know the width of your fabric: you can’t work zero-waste without knowing the width of your fabric, given that this is precisely what defines your design.