One of the joys of Dystopia Rising (DR) is the opportunity to craft props. Recently, my character acquired a shield built from an old sign she found while visiting the Eternal Kingdom (i.e. the United Kingdom).
The shield itself was built by another player using insulation foam and duct tape, which makes it incredibly light (a huge benefit for me considering my physical limitations in this game) as well as affordable (which is never a bad thing).
I did the paint job, which I completed in the span of a day.
Step 1: Plasti-Dip
Paint, including primer, does not stick to duct tape well. So the first thing I did was spray it with Plasti-dip, a spray-on rubber coating. Plasti-dip is used on a lot of DR props because it remains flexible.
Step 2: (Optional) Sketch Out Design
I’m eventually going to cover the entire shield in spray paint, so whatever I draw here will be obliterated. However, I wanted to lay out the lettering so I could plan the location of the rust. I’d hate to render the slogan unreadable.
Do not use tape to mark straight lines. Even painter’s tape will rip off the Plasti-dip. The light gray areas in the picture are where I accidentally pulled off the Plasti-dip and tried fixing it with gray primer. It didn’t work, so I sprayed on more Plasti-dip before moving to step 3.
Step 3: Apply Rust
I made the rusted area by stippling three different colors of acrylic paint. To stipple, get a small amount of paint on a dry brush, then tap the ends of the bristles against the shield surface . This creates lots of paint specks rather than fields of color. It works best with an old, worn brush, and there’s a good chance it will ruin whatever you use, so plan accordingly.
I start with black, then red, then yellow. You can also use orange, but I found that stippling red and yellow together created enough orange I didn’t need to actually paint with orange. I work in sections, because I want the paint to remain wet as I’m adding layers so everything mixes just a bit. If it gets too murky, let it dry and stipple more paint over it. Repeat until bored.
Be sure to paint every area where you would like at least a little rust to show through.
Beginning to stipple with black paint. Note the stippled texture. 
Finished rusted areas. I have hidden far more of the lettering than I am planning on being obliterated in the final product.
Step 4: Salt
Pour a thick layer of salt over where you would like the rust to be completely visible. Scatter lesser thicknesses of salt over the rest of the rusty paint. I’ve placed the shield on a couple large trash bags to catch the excess, of which there will eventually be a lot.
Step 5: Spray Paint
Brushing regular paint over the salt would push it all off the shield, so spray paint is a must. Cover the entire surface with your background color (in this case, blue), being careful not to blow off the salt.
Step 6: Dump the Salt
Quickly turn over the shield so the large chucks of salt fall off onto the trash bags. I did it while the paint was wet because I wasn’t sure how hard it would be to remove it when dry. Be fast so the salt falls off rather than slides over the surface and leaving streaks.
Let the paint dry.
Salt applied to the rusty areas. 
Spray paint applied and major clumps of salt removed.
Step 7: Stencil the Design
I draw out my design in chalk (again) and then stencil with acrylic paint. This gets a little tricky because the salt has made the surface bumpy and the stencil doesn’t lay flat. I stippled the paint with a makeup sponge, which creates a nice, uniform texture. Avoid painting over the revealed rusted areas, since the lettering would have flaked off with the rest of the paint.
Step 8: Scraping the Salt
Take a razor blade and scrape off the remaining salt. Be gentle and at a shallow angle. You want to remove the salt and the paint on top of it, but not the rusted paint or Plasti-dip underneath. I found running the razor blade backwards worked pretty well.
Unless you are very dedicated, you’re not going to get all the salt off. That’s fine as the rough texture mimics how paint bubbles up when metal rusts underneath.
Step 9: Sealing
I don’t want my paint flaking off every time it gets hit, so I’ve put a protective spray coating over it. I went for a matte finish since I want to imply old and broken down.
I’ve used this technique for other props as well, such as my drinking bottle. In that case, I painted the entire bottle rust and added the salt while the rust was still wet, because otherwise the salt just slid off the curved surface. There was also no plan as to where I put the salt, as I can’t expect it to stick in any particular pattern. Then I spray painted it black and shook off the loose salt.