If you have not already done so, check the
List of Huntorials and take a gander under Bio Painting. Also,
PredatrHuntr has compiled a great list of Huntorials in his profile, as well as created an AWESOME
Bio Helmet Reference Thread. Definitely check them all out!
Personally, for my
P1 Stunt Bio, I will be going with the following tried and true method, per ptgreek, which is also the way I knocked out my
Spartan Armor:
1. WASH the bio with dishwashing detergent. Some people haven't stated this previously and unfortunately a few weeks back, another member found out the hard way and had to strip his paint job.
2. Base coat with a cheap rattle can of auto primer. I found a black one at Home Depot for $3-4.
3. Depending upon bio, and ultimate goal, you can spray a siler coat (Again, rattle can) on top of that. I'm still up in the air on this step.
4. Move on to acrylics. I use the bottled
DecoArt Dazzling Mettalics, Folk Art, and Americana found at Michael's, over in the crafts section, not the airbrush acrylics, but that's just me. Pick a couple of different colors and have some fun mixing the colors up. I just mix different shades as I go, a little at a time, on a picnic plate.
5. Use a sponge, brushes, fingers, etc. to apply and blend your colors. You can also go back while it's wet and pull some of the paint off with paper towels. You can further take a scotch brite sponge and take off the dry paint with some water, but be careful because the colors will start to bleed together and you'll lose the mottled look.
6. Some guys clear coat. Some guys don't. The big pro to clear coat is it makes the paint job more resilent to scrapes. I had a guy spill beer on my Spartan greaves and it totally jacked up my pack job. On the downside, as has been pointed out to me, clear coating takes away from the mottled appearance. So, experiment and go with what you are comfortable with as a final look.
Many more steps can be found in the threads above, as well as other tricks for blast marks, and further weathering. Best of luck!