Yellow is a double edged sword. It's a real pain to get a good basecoat, but then the translucency makes highlighting very easy.
On these guys I airbrushed on a basecoat of Tamiya acrylics. Yellow with a tiny amount of red in it. I then washed that with the new Gryphonne Sepia in all the recesses, and then Devlan Mud in some of the deeper areas. Over that is Golden Yellow and then some Vallejo Sunburst Yellow. Again, easy to blend with such translucent paint.
As far as the decals go, this is the kit:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXESK4
Or something very close to that...
It comes with some clear and some white backed decal paper. You print on that with the inkjet, you seal it with a sprayed clearcoat, and there you go. The clearcoat is a real wildcard. I'm not sure what the right amount is. I decided to spray a little more than I thought I should and err on the side of a thicker, stronger decal. Even then, they were thin and fragile.
I used a graphics application (CorelDraw is good with vector drawing) to make my decals. First I scanned in the normal Marine decal sheet for scale, then drew over that. It's tricky to try to think of every possible decal you might want for a whole army, but you have to, since you print the whole sheet all at once. I just tried to cover all the bases with fists of different sizes, arrows, etc. etc.
It helps to print out your graphics on a regular sheet of paper first so you can check them over. It's also good/necessary to do this because you can then see where the printer will hit the paper, and you can tape the decal sheet right where it needs to be. I used scotch tape, it worked fine (but the scotch tape will rip the decal film off the backing, so leave a bit of room at the edges.
Note that the decal paper is very glossy, so most modern photo printers will do great on it. I was pleasantly surprised when the decal paper looked twice as sharp and nice as the normal crap paper I tested on.
I actually cut the provided sheet in half, and used only one for my decals. That was more than I needed, since I packed them in pretty tight. This gives you more mileage from the kit, so worth doing.
The resulting decals are pretty good, but VERY fragile as compared to
GWs. I did use a solvent, but I diluted it, and was very careful with it. If you hit the sweet spot, these decals are great, as they get very soft and settle right into place (
GW's are a lot tougher and more stubborn). The problem is you're more likely to melt the decal, have the inkjet ink leak out, etc. so be prepared to abort a given decal, chuck it, and try again (so put more on your sheet than you think you'll need).
Also, because the decal sheet is just one big contiguous block of backing, you have to trim the decals down as close as possible by hand. Another bit of effort you don't normally need to do.
The final issue is white. You can only get the colors your inkjet prints, so that's all of them, minus white. They offer white backing film, but I found this to be translucent, so pretty much worthless. If you need white, you might consider freehanding it in afterwards, or painting it on under where you plan to put the decal.
All in all the stuff requires care, but I think they're an easy way to get much MUCH nicer results than even the best freehand work. All the decals in these images happen to be black, but I have some with green in them, and could have any color, really.
