Back in my modelling days, for primer I liked to use this stuff called gesso, you can get it in a spray can.

I liked it because it absorbed paint better and when you sanded it it got as smooth as glass.

Heres some pics of a keyboard that I am doing right now, not quite done. I used krylon indoor/outdoor for the red, black and ivory. the dark gray is just primer because I couldn't find anything that matched that color. The light gray is just some cheap stuff cause krylon didn't have flat gray. Got them all at Wal Mart.

couple coats of primer, sand down then several thin coats of color.
and it helps if your primer is either white or a lighter tint of whatever color is going on top.

and I plan on painting this pixelated mushroom sprite on the 10 key section but Im not sure how yet.
at first I thought stencils but will probably do it by hand.

oh yeah and I don't really think acrylic would be your best choice, not durable enough unless you put a clear overcoat on it then it would work.

Oil based paints aren't going to work well on plastic without primer, I recommend priming it first with a neutral plastic primer or base coat that matches your biggest fill and then using the acrylic Decocolors over that, finished with clearcoat.

I used to rock the pilot super jumbos with DOT3 and a drop of fish oil, so I know the score too homie.

Deco paint markers maybe sharpie paint markers and sum clear gloss and your finished nothing to complicated yo. I graff it up :3 so I know a thing or two about a thing or five

That's real clean. You could probably do that in a meticulous fashion with acrylic paint markers and a careful masking, but I haven't tried to paint anything like that small scale before.

Somthing like this, it's just a draft, I may make my name central to the design though.

Tell me what you think

I got sloppy and did mine with no primer, but it's also a plastic bonding paint, so that made it ok.

This is the same stuff I paint LSDj keyboards with; it works pretty well.

You see this quote? You just read the bible, right there.

EDIT: To clarify, I don't think you don't use much more paint this way, but you want the thinnest coat dried to the touch over and over until you get an even coat, not sloppy thick coats that don't dry right before you start the next coat.

yeah ditto what telerophon said about painting like models.
same technique.

and always use a primer.

I like to wash with windex and let dry completely before I put on primer, and spray enough that you can sand down just a little cause the spray pattern of cans sometimes produces texture.
I like several thinner coats too, with ample dry time between them. you use more paint that way, but the results are worth it.

Just finishing it.

Yo show me the graff you wanna do

What I have come up with is a stencil set with a jig, so it will keep the gameboy in precise place, I have made the design on photoshop and each layer will be printed out, glued to card then sprayed, I will be using a wide nib so the paint is more of a cloud of paint to settle on the gameboy, it will use  a hell of a lot of paint but will give it a better and even finish.

Was it for plastic? You can get Tamiya polycarbonate spray paint for model making at hobby shops, CM.O member Evil Scientist has used it with much success for some of his custom mods.

As for doing a graffiti style piece, I'm not going to be able to give good advice about how to scale down a full-size piece. The issue with recreating graffiti at small scale is the tools: you need both an airbrush and a firm command of the airbrush as a means of artistic expression. A typical full graffiti piece done with rattle cans is about 8 feet X 12 feet, so you would be scaling down immensely. If you really want to try it, your best bet is probably paint markers. You'd still have to spray your case with plastic primer and a base coat, though.

As an alternative, may I suggest you design a tag-styled linework case and clearcoat over that? I think that would be a lot easier to do at that scale. Not that I'm an expert on graffiti or anything…

Painter's tape or masking tape, the same way I did the lines on my case. just make sure your mask is on securely or you're get overspray like what is by my A Button. Paint a base coat that's white or the lighter color, and then do the checkerboard in the darker color over that.

I was about to make a similar thread, but I suppose I'll just ask here, what would be the best way to go about painting a checkerboard pattern on a DMG?
And if I wanted to do some more detailed stuff, IE painting a character over the checkerboard pattern, what would be the best type of paint to use?

I bought some acrillic paints for hobby painting and it just goes on horribly, glad I used a scrap case, what else apart from spray paint can I use, I want to do a graffiti piece on it. I guess I could use different stencils.

I really don't want to be that guy who tells you to search before posting, but there's a ton of information about this both on this forum and all over the internet. FYI.

As for painting, the best way to approach it is like you are building models. All of the same stuff you would use to paint plastic models is stuff you can use to paint DMG cases. The sky is the limit!

Here's my last paintjob:

As for my personal experiences, I did the DMG above with DupliColor vinyl spraypaint, used to do vinyl automotive interiors. If you can get spray vinyl die, that's better and leaves a finish like the original game boy, but that's hard to find. I've never seen the stuff in person.

If you're not going with metallic paints, I like satin finish the best.]

gloss looks good, but its easy to mess up and gets smudgy and slighty sticky to the touch

The Krylon satin ivory and black look great especially together