First, start with your canvas. It should be 512x384. That's right... double the size of a standard DS screen.
This is how I do my sprites: I draw the basic guidelines first, to get an idea of the pose. For these, I use a size 9 brush (size depending on pen pressure) and I try to use a lighter color (grey-ish, so it doesn't get mangled with the clean outlines.) Then, I draw the clean outlines on a different layer so that I can color later. Use a size 2 or 3 brush where the size is fixed - not altered by pen pressure. After you're done with the clean outlines, you'll be able to start coloring on a separate layer. For Phoenix Wright sprites, 16 colors are used. Apollo Justice sprites use 32. Try to keep your colors within that limit. After the coloring and shading are done, resize the canvas so that it's 256x192 (bicubic is the best setting.) Make sure to also delete the layer with the rough sketch. This is the tough part: on the bar at the top of the screen, you'll see a button labeled "image." Click that, and a drop down menu will appear. Hover over "Mode" then select "indexed color." You'll be asked if you want to merge layers. Say yes. After that, a window will appear. There will be a selection reel entitled "palette." From that, select "Local (selective)", set the amount of colors to 17, and then make sure that the "transparency" box is checked.
The end result:
![Image](http://i42.tinypic.com/sxd6js.gif)
It's not the best sprite I've made (and it's not the most original...) but it works!
![Pearl Happy :pearlhappy:](./images/smilies/aa_icon_pearl_happy.gif)