Well, For a good paint job you need to layer the paint. First sand the armor nicely with a light sand paper like 600 grit. Then give it about three coats of primer and let that dry for a couple of days. Then spray on a couple of coats of silver and let that dry for a couple of days. Then tape off scratches and damage where ever you would like. I suggest using electrical tape or some kind of liquid mask. Then spray on the first color that you want under the top coat. After about 10 to 15 minuets take the masking off. Then after the paint has dried completely mask off those same spots as before except a little bigger this time. Repeat this with the other colors. Then after all the colors are done spray the armor lightly with flat black to give it a dirty look. Also i suggest searching for weathering techniques in past threads here on TDH.
Mask the silver
<img src=http://200.72.163.179/cdref/tdh/General/masking1.jpg>
Paint the first color
<img src=http://200.72.163.179/cdref/tdh/General/masking2.jpg>
Mask off the scratches
<img src=http://200.72.163.179/cdref/tdh/General/masking3.jpg>
paint the second color
<img src=http://200.72.163.179/cdref/tdh/General/masking4.jpg>
mask off scratches
<img src=http://200.72.163.179/cdref/tdh/General/masking5.jpg>
Then the top coat
<img src=http://200.72.163.179/cdref/tdh/General/masking6.jpg>
Then dirty it up a bit
<img src=http://200.72.163.179/cdref/tdh/General/masking7.jpg>