Here is a quick and straightforward guide on what will give you a good start if you want to get started on painting miniatures. I am not going to discuss getting miniatures or preparing them for painting (cleaning, assembling, priming etc). Just a list of things of paints and tools that would give you a good start on this.
A NOTE: I will not mention any specific brands of miniatures paint here, because all major manufacturers have some good and some bad products, and what you should use is what you can get your hands on. I have things I prefer, and I use paints from like 5 different companies.
A SECOND NOTE: I will assume you're painting sci-fi or fantasy miniatures, as those dominate the hobby and market.
A List of Paints
I would start by acquiring the following colors
- A white
- A black
- An off-white or bone color
- A green
- A deep and rich red
- A deep blue
- A yellow (Whichever one you get will suck. Don't worry about it)
- A silvery metallic paint
- A copper or gold metallic paint. Ideally both
- A black wash/shade
- An umber wash/shade
- A sepia wash/shade
- Between 1-3 shades of brown, tan or ochre. Preferably ones that are not too similar to each other.
This will get you enough to paint most fantasy and sci-fi minis. You should mix your colors to achieve more complex tones, using black, off-white or browns to make colors lighter or darker. From here on you can expand your collection of paints by getting individual things you need for whatever it is you're painting. Stuff I would generally get, if you need it, would be
- Some kind of purple
- A bright fiery orange (those are hard to achieve by mixing most miniature paints)
- Any other bright or very vibrant color you might need
- Colored shades or washes. I increasingly prefer to just use contrast paints and dilute them with some contrast medium+water to make them into a wash.
A THIRD NOTE: I would generally not buy any "skintone" labeled paints. Leaving aside that those more often than not simply are just a very pale, white idea of what a "basic skintone" is, you can achieve a decent looking skin tone by simply mixing your off-white with some kind of warm or reddish brown (either one you already have, or mixing any brown with a bit of your red).
Other Tools
Obviously, if you're painting you'll need a brush. There are a billion opinions (most of them from people who have no idea what the fuck they're talking about, but simply regurgitating shit they heard from someone else) about what is the right and correct brushes to get.
Ignore all of that shit. More likely than not, you're painting 28mm scale figures, and for that you can do 99% of your painting using just a number 2 sized brush, synthetic or natural hair bristles, that can maintain a fine point.
That last bit is the only truly important thing in miniatures painting. You want a brush that will not lose its top as soon as you put paint on it. How expensive that brush will be for you depends on where you are and what you have access to. I've painted minis using just random brushes i bought off Amazon and it's been fine. I mostly use an artist's sable hair number 2 brush I can buy reliably at a local art supply store. It doesn't matter.
Next you'll want some kind of a palette to put your paints on. For this you can use any non-pours surface really. A spare plate, a single smooth ceramic tile, just a cheapo plastic palette you can buy from the arts supply isle of your supermarket. They'll work fine. Don't bother with a wet palette for now. They're good, they're nice to use - you do not need one at all.
You will also want a thing to keep water in, and some paper towels or a piece of cloth to clean your brush on as you paint.
And that's it. You can acquire most of this in pieces or buy a starter set that most manufacturers usually sell.