You just opened your new game. It contains several piles of plastic miniatures.

Preparation
The first thing to do is separate your minis by type.

So, let's say you find your new game contains 12 foot soldiers with swords and shields (4 have moustaches to denote that they are hired mercenaries), 24 peasants with pitchforks, 24 mounties with hockey sticks and 61 generic townsfolk who come in 4 different poses.

Get a nail file and file off all of the sprue from the minis. And make sure your area is well lit. (If not, you are likely to get eaten by a sprue.) Then wash all of the minis. Warm water and soap. Make sure you get behind the ears and don't forget the naughty bits. Note that this is very difficult to do with a standard bar of soap. You may want to get a razor and shave the soap down into a little tiny soap bar for each mini, if you have the time.

After washing, the minis are ready for the primer. Note that you really should use a primer meant for miniatures. Using rimfire ammunition primer will likely blow your army to bits way before you get to play with them.

If you plan on painting your minis "assembly line" style, you will want to get yourself some white glue, a box of ice pops and some hot cocoa. Eat a few ice pops. Glue several of the same style mini to the ice pop with the white glue, so you basically have a little stick with 4-5 of the same guy on it that is really easy to manipulate. You'll want the cocoa just to warm you up after eating all of the ice pops.

Painting techniques
Painting techniques include:
glazes (very liquidy mixes of bright colors that go into the recesses of a mini)
washes (very liquidy mixes of dark colors that go into the recesses of a mini)
drybrushing (if you can't figure out what that means, you need an even more beginner guide than this one)
blends (this takes too much time, so you won't do it for a game with lots of guys unless you plan on either never actually playing the game because you're too busy painting, or you plan on winning an award for most time spent painting a game)
Al Fresco (this means painting outside or eating cold pasta. After your significant other kicks you out for covering the dining room table with miniatures and paints, be prepared for both.)

The easiest way to paint miniatures quickly is to pay someone else to do it.

Failing that, what you'll want to do is spray prime darker guys and guys wearing armor in black. Note that if you are painting ninjas, you are now done. Spray good guys and guys in bright clothing white. Please note that this should only be done to miniatures, not simply guys in bright clothing you meet on the street, although there may be exceptions, particularly if you live near Richard Simmons.

Some people drybrush first (which means using no paint on the brush and giving you an excuse to not rake the leaves while it looks like you're doing something) and then paint a transparent layer over that. Some people paint base colors, then drybrush and wash. Now, if you drybrush and wash, it's probably because you just got up and can't find the toothpaste. Calm down, be patient and try again. You can paint the minis later.

Always paint minis from the inside layers out. This means paint items in the order you would put them on in the morning. This will prevent you from having to repaint the outer parts as you try to get to the inner parts. Again, just like you dress yourself: Skin first (unless various entrails are showing), then pants, shirts, belts, socks, shoes (note you can do both socks and then both shoes, or one sock and shoe then the other sock and shoe. Either way is fine, and obviously one is preferred in Europe), then another shirt as your significant other points out the marinara stain on the first one, and then the coat, cloak or cape. If you normally put on a cape in the morning, don't you have more important things to be doing besides painting minis?

Finishing touches
Finally, weapons and such get painted. First paint them black. Then get a metallic color, barely touch the brush to it, wipe it off and gently drybrush against the grain - but without being too insulting. If you paint your weapon right, it will look exactly like it did if it were a metal mini and you hadn't painted it at all. Basically, when you perfect the technique to look like you forgot to paint that part, you've got it down. Let us not forget the scandal several years back when the national award for best armored mini was proven to actually be unpainted.

You may then apply washes and drybrushing to bring out the details of your figures, assuming you have not layered on so much paint at this time that your exquisite designs now resemble uncooked potato bits.

Finally, let the minis dry for a few days.

After you complete your painting, you will probably need to find a new gaming group, since it has been so long since you left the house that they have all moved away. There's also a good chance that by the time you are done, the second edition will have been released and the Mounties units are no longer a usable unit, having been replaced by two weasels and a sheet of foodstamps.