My personal army painting recipe for the main elements (uniforms, armor, basing, etc.) in my Astra Militarum army.

Prime

I prime these models black (any black is probably fine) and then hit them with a zenithal of Vallejo Grey primer (but any white or off-white is probably fine).

Grey Fatigues

1. Basecoat with Mechanicus Standard Grey .
2. Wash with Nuln Oil or any black wash you like.
3. Do a broad highlight with Dawnstone - raised areas, kneecaps, etc.
4. Then a tighter edge highlight with Administratum Grey .

Tan Fatigues & Overcoats

This one is a little less solid than the others, and I may adjust the recipe over time. The color it produces is good, but getting solid coverage can take a while.

1. Basecoat with Tallarn Sand .
2. Wash with Agrax Earthshade . If you're using the old, larger pot of Agrax, or a heavier brown shade like Pro Acryl's Brown Wash or Two Thin Coats' Battle Mud Wash, then mix it 50/50 with Lahmian Medium .
3. Layer back up with Tallarn Sand , avoiding the recesses.
4. Do a chunky edge highlight with Hobgrot Hide , hitting raised areas, knees, folds, etc.
5. Do a final edge highlight with Skeleton Legion . Ushabti Bone is a good stand-in if you don't have Two Thin Coats paints.

Brown Overcoats

I like to mix it up with this army and paint overcoats and occasionally fatigues in this color rather than the yellowish tan above. I think the two colors fit together while emphasizing the inconsistency of the Chem-Dogs' gear.

1. Basecoat with Steel Legion Drab .
2. Wash with Agrax Earthshade .
3. Layer back up with Steel Legion Drab , avoiding the recesses.
4. Do a chunky edge highlight with Baneblade Brown , hitting raised areas, knees, folds, etc. Because there's a pretty big value jump here, consider thinning your paint a bit more than usual – not quite a glaze, but lighter than a regular edge highlight.
5. Edge highlight with Karak Stone .

Blue Flak Armor

1. Basecoat with Jade (That's Dark Jade, not regular Jade). If you don't have it, Incubi Darkness works just fine.
2. Do a chunky edge highlight all around the edges of the armor with Twilight Sky . This barely needs thinning as it's an Air paint, but if you don't have it, use Stegadon Scale Green and thin it quite a bit.
   FYI, I skip this entirely on very small pieces of armor or very detailed ones, like on Genestealer padding bits. It's not necessary there.
3. Stipple and make little scratches with Sotek Green .
4. Finally, dot the corners and sharpest edges with Temple Guard Blue .

Leather

1. Even if your zenithal prime has been run roughshod by yellows and tans and blue, Wyldwood should still work as a basecoat for your leathers. If it doesn't, just use a nice dark brown like Dryad Bark or Rhinox Hide.
2. Edge highlight with Light Umber , which is much paler than it looks here. Gorthor Brown from Citadel will also work.
3. Edge highlight more selectively with Baneblade Brown .

Aquilas and other Whites

Lots of ways to get an ivory color here. I generally base with Olive Flesh and highlight with Bold Titanium White , but any warm off-white and then pure white will do the trick.

Eyes & Lenses

1. I like bright lenses and lights to add some contrast to this army. For goggles, glasses, and scopes I usually use Wild Rider Red and then add in some Troll Slayer Orange on either the top or bottom of the lens.
2. For headlamps, headlights, and other more industrial lights, I basecoat in a pure white like Bold Titanium White and then put a coat of Frostheart on top.

Savlar Skin

In my Chem-Dogs army, I use a variety of skin tones, to represent possible off-world prisoners that had been condemned to Savlar. For the long-term residents, who are all bald and often have weird tattoos, I stick to one particular and sickly skin tone.

1. Basecoat with Rakarth Flesh .
2. Wash the recesses (eyes, beneath the nose, etc.) with Targor Rageshade . Go back over any spills with Rakarth Flesh if you need to.
3. Highlight the skin with Olive Flesh .
4. Highlight the sharpest points (tip of nose, brow, etc.) with Pallid Wych Flesh .

Black

I do lots of stuff in black – boots and gloves sometimes, cables and pipes, weapons, grips, etc. It's a pretty standard recipe.

1. Basecoat in Black , or literally any black you like.
2. Chunky edge highlight with German Grey . You could use Eshin Grey in a pinch.
3. Edge highlight with Dawnstone .
4. Dot the corners, if it's something blocky like a lasgun, with Administratum Grey .

Basing

1. Get your texture on. This can be sand, sand & rocks, texture paint – doesn't really matter. Do what you like.
2. Basecoat over the texture with Rhinox Hide .
3. Do a heavy drybrush with Indian Shadow . If you don't have that paint, you could probably use something like Citadel's Gal Vorbak Red or Army Painter Warpaints Fanatic's Blanched Berry.
4. Do another drybrush with Cavalry Brown . Not a ton of good stand-ins for this paint, but some options are Pro Acryl's Burnt Red, Citadel's Word Bearers Red, or Two Thin Coat's Evil Eye Red.
5. Then do a final drybrush with Khorne Red .
6. For rocks, I usually paint them according to the Grey recipe above, but wash them in blue rather than black – something like Drakenhof Nightshade .
7. For tufts, I use Army Painter's inexpensive Deadland Tufts. Rim the base in any black you like.