At it’s most simple description, in color blocking we draw what we see in front of us one shape at a time. Here are the most outstanding aspects of the exercise:

1. use NON REPRESENTATIVE COLOR! What do I mean? If you match brown to hair, skin to skin, shoe color to shoe color, etc, etc, then you’ll have a completely different  experience.nce you start drawing what you see without matching the colors, your brain changes its orientation from drawing symbols like “hair” “face” , “shoe”, “hand” and starts to zoom much more specifically into the SHAPE of the (PURPLE?) face, the (ORANGE?) hair, etc.  
2. LINE “DISAPPEARS”- Well, not really. There are no LINES, but every shape has an edge. The line and the shape are fused into one. 
3. USE OPAQUE FLAT COLOR for each shape. This helps you truly see and feel the impact and character  of every shape, and to fuse the shape to its edge (mentioned above)
4. PURE SILHOUETTE For many of you, this will be the first time you create a drawing that doesn’t hold the white of the paper within it, which is a huge step! The entire drawing is full of tone, which is a great warmup also for how we work with gouache.  You’ll be noticing the micro-silhouttes (of a foot, a bag, a cuff, bangs, collar) as well as fine-tuned in to the MACRO- overall silhouette of the fashion garment , pose, figure, and look.
5. PROPORTION once you begin the drawing, carefully lay down each shape in truth compared to the first shape. This will keep your proportion accurate. DON’T  try to adjust the size of things just to fit the pose onto the page. Let the size of the first shape you drew keep you consistent with the relative size of every shape you capture in your drawing.
6. PACE YOURSELF I suggest setting a timer for 10 or 15 minutes and letting the drawing be done when the timer goes off regardless of how “far you’ve gotten”. There is magic in this because it slows you down and brings you totally into presence with the drawing experience. it’s very meditative and actually VERY CALMING in a beautiful way you’ll only know as you experience it. There is no racing to the finish line!
7. EDGES use every thing you know about contour drawing to capture the character of the edge of each shape as you go.
8. ORDER there is no rule where you start, finish or proceed.I often start with the hair shape, but sometimes I work my way down the page from the top left to right and other times I go down the page just on the left side before ever tackling the right side. Follow your intuition.
9. CONSTRUCTION use your knowledge about fashion or costume garment construction to recognize where you see seamlines or layers, and make sure to switch colors wherever you see those breaks in shape.  The part in the hair, etc, also means it’s time to change colors!
10. LIGHT AND SHADOW sometimes I’m drawing an image that has simpler shapes and find I’m finished quickly (other times I don’t come close to finishing capturing all the shapes) but if I “finish early”, I will sometimes take colors into each shape at the end  and lay down the shapes of the shadows I see. Learning and practicing to see shadows as SHAPES is a VERY VERY powerful exercise for effective fashion illustration drawings!