Introduction
So, I decided I'd have some fun making my own playing mat for Armada (and X-Wing if I really wanted). We have several mats available to us, of course, but none of them fit the huge 6x3 size that we want for our games. We could fit two 3x3s next to each other, but 1) it can look a bit tacky unless they're two of the simple stars-only ones, and 2) you're looking at around $90 for those!
What if you could do it with a couple hour's work, and about a third of the cost in materials?

Materials:
1. 6 x 3 ft surface. I went and got some black cloth. Wool, I think. I dunno. I wear $5 black walmart t-shirts all the time. Fashion ain't my thing. But, it is heavier than cotton by a good bit, and I figure it'll hold together better over time. Since it's a bit heavier you avoid some of the slipping and sliding problem you might have if you used something like cotton. The downside to cloth, of course, is that you have a less solid surface to work on, so you have to be careful not to mess up your game by putting your hand on the cloth and then slipping it off. You could use poster board, particle board, or whatever you want. I picked the cloth because it's easy to pick up, roll up, and take from place to place, but it's personal preference.
2. Paint! You'll need 2 colors of paint and one white paint. For the surface area, you really won't need much. I got 4oz of each and had leftover. I got Red, Navy Blue, and White (no star spangled banner, don't worry). It's good to get two colors that you can mix to get another in-between color. I got these two so I could make some purple as well. I wanna try doing yellow and blue next time, so I can get some green mixed in.
3. Brushes. Two sizes of brush: one big one (I used a 2.5" wide brush) and a smaller brush (1" or so is good, maybe even a bit smaller).
4. Paint pallet or some such. Just something you can put your paints on to mix and all that.
5. Imagination.
6. Tape Measure.
7. Paper Towels (You'll be using half a roll for this, if you're anything like me x3)
8. Water bowl (for cleaning your brush out between colors)
Process
1. Squirt out some of your darker colored paint (in my case my navy blue) onto your pallet, as well as some blue. You'll need a good healthy amount of both, but keep them away from each other from now (opposite sides of the pallet).
2. Using your large brush, pull some of your darker colored paint and your white paint together, mixing them together to get a good, medium tone of your darker paint (my navy blue became a nice, medium blue). Try not to go too light or you'll start to fade the color too much. You also shouldn't perfectly mix the paints together. Having some variations of lighter and darker will help make more varied patterns in your end result!
3. Load up your brush with paint, wiping off excess on your pallet and then use a paper towel to further get some more paint off. This is the hardest technical part of the entire process: making sure you don't have too much paint on your brush. You want a nice, even stroke, and getting too much paint will leave you with a nasty looking blob.
4. Using the side edge of your brush, create arcs of paint on your surface. Play around with these shapes, in combinations. You want to get a semi-solid line that has a bit of a chalky texture to it.

5. Play around with all sorts of different designs! Here's a basic one for ya.

6. By now the paint on your brush should have thinned out. If it's still got a bit on it, take the paper towels and thin it out a bit more. You want to have a very light amount.
7. With your lightly dusted paintbrush, set your brush on the arc you made and strike away from your arc, creating a sort of bushy pattern. Think of this as smudging the line out. We've all seen pictures of galaxies and nebulas, so you should have an idea of the swirling sort of look they should have. Follow the curve of your arc as you dust away from it to create that swirling effect. (In the picture, correct method on the left side, while right side shows what happens if you place your brush and then move towards the arc, giving you those flat areas rather than our nice splayed out dusting)

8. Continue this all around your arcs till you have very nice dustings. Use the darker paint on your pallet (the paint not mixed with white) to dust further away from your central arcs, allowing the colors to fade towards the black. If you've still got some brighter paint left, touch up your arcs and blend them together so they don't look so much like individual lines.

9. Here's another cool looking design I like, and it's easy to do. One large semi circle overlapping a smaller semi-circle, with a few little arcs breaking off of them.


10. Keep making these patterns spread out around your space. You're going to be incorporating three different colors in this, so leave some extra room between for the other colors. However, your dark one should take up about half of the space right now, since our other colors will overlap the dark colors later on in some areas.
Note here I also added the 3 foot lines. It's helpful to have some extra cloth for setup area on the side. We've got our first two colors down now, which are the navy blue and the lavender/purple (which I made via mixing in some red with our remaining blue).

11. With our second color, make sure you go back to your first color's areas and give little dustings to create some contrast within the swirls.

continued...