I know it has been said many times before but hair spray tech

You don't need six hours for the hairspray to dry,waiting that long will make it difficult to remove the hairspray.The hairspray just needs to air dry.

Just a suggestion,it's more expensive then hairspray,but take a look at the AK Chipping Fluids.They are designed for modeling,easy to use,and won't make your model smell like a beauty parlor.I love the stuff,it works great.

thanks guys now all we need is a sticky lol

Your basically spot on the only  step your missing is a seal coat .

 I thought you might  like my attempt at a  synopsis of  a ref. I have on a Panzer grey Mark IV. Sorry if it's still a bit long in the tooth. I  didn't want to leave out too much detail.

* The filter step of the hairspray technique involves painting the model in its base camouflage colors

    and markings have been applied  and sealed using clear acrylic

*A couple of moderately heavy layers of hairspray are applied over the whole model

*A thin , patchy coat of ( well thinned)  acrylic white paint is sprayed over the base grey color. ( the author states it can be left overnight but he likes to get  straight to work on it. )

*Tools and materials used for the process: warm cup of water,  wide flat brush for painting water onto

  surface. Medium sized brush and finer brush that are cut down to resemble stubs ( used to remove

  paint).  A pin needle and sharp toothpick ( for small scratches and scraps)

*In order to start the the wearing process of white paint,  apply water to small sections at a time.

*After a couple of minutes the water will soften the hairspray underneath the paint. Use a small cut 

  down brush to remove small areas of white.

*For small scratches  and chips apply some more water and drag the needle lightly across the surface.

 Avoid scratching the base coat in the process.

*Softer contrasts between the grey and white are achieved by lightly dry brushing  grey  with a flat  brush.

  Achieves a subtle worn down appearance

 *A dilute wash of dark earth and small amount of burnt umber oil is applied liberally onto model. This  

  tones down harshness of  the white .

 * Shadows around the smaller details can be strengthen by applying  a dark pin wash. Wetting the area around the details with thinners first will help  this.

 *A dilute black wash is dotted around detail -  the   previous application of thinners help draw the wash  

   around it.

 *Acrylic white is used to add fine highlights along edges of the scratches and paint chips.

 *A dirty brown wash of light earth is applied on the horizontal surfaces for depth and grime.

 *Use a black pencil to darken edges where white paint has worn away.

*Using a clean brush dipped in thinner drag down  the oil paint to represent subtle rust streaks.  Avoid

   over doing. 

  The End

You pretty much got it, but don't forget to spray the basecolor on top of the hairspray, which is the color you want to wipe away, revealing your color underneath.