writes:
Some of my projects proceed very slowly. Take my Grey Knights. I finished the leader in 2012, the first squad in 2016, and four years later, I'm back for more! 
Now when you work at glacial speed, it's important to keep notes or you'll forget the painting techniques you were using. Fortunately, as you can see if you follow the links above, I've documented everything. Alternately, if you don't have a way to publish your results (got a blog?), you can keep a painting log for future reference.
I'm using the same basic Grey Knights boxed set, but building them up this time as Purifiers (which I can have in my basic force, due to my choice of leader). I'm keeping the same color for the body armor, but switching from red-and-silver accents to black-and-gold accents. And my concept this time (this is space fantasy, right?) is that the members of this squad have inherited the hypothetical geneseed of stars from a particular beloved sci-fi show.
Construction
Here I've assembled the figure and prepared it for priming. I'm leaving some parts separate at this stage for ease of painting (backpack, shoulder pads) or because they would make it harder to paint something else (right arm). The Knight of the Flame leader figure gets the big sword and the unarmored 'bare' head.
Then I wanted to give one of my Purifiers the big two-handed Daemon Hammer… but apparently I've already used up the arm pieces needed! I could have bought a second boxed set (the correct answer!), or I could kludge together other pieces and make them fit. Feeling rather clever, I put a wire through the main body, and rig the arms to fit into place when everything is painted. What can go wrong?
Looking at the remaining parts, what can I still build? Well, OK, the troops with the dual falchions are kind of ninja-cool and fun to pose. So I build two of these. In one case, I glue the arms on because I don't think they'll block my painting; with the other figure, I leave off an arm and a hand-with-falchion.
And the final squad member is a basic dude with gun and sword.
I've used plastic cement to put the parts together, and gotten my files out to make sure the seams are not too obvious. I added metal disks to the base to give the figures some heft, and for storage in boxes lined with magnetic sheet. They are ready for priming!
Painting
Everything is now primed flat black with spray paint. Any spots missed are touched up by hand.
Now comes a generous drybrushing with my go-to dark gray paint, Delta Ceramcoat Charcoal.
Then a light drybrushing with a light gray color. This will look extreme and grainy, but when followed with a black ink wash, you get the battleworn look I'm going for.
When the ink wash is dry (wait 24 hours), the details are painted. I used a gold marker for much of the detailing. The swords are repainted dark grey with just a touch of metallic drybrushing for the 'power sword' look (no 'glowing' swords today!). Bases painted black, with black sand glued on top. Sealed with Dullcote.
The painting went surprisingly quickly. Now I'm wondering why I took so long with the previous figures! (Maybe experience counts for something?)
Finished Purifiers
And here they are!
The final ink wash is almost magical in its effect.
The back view – the backpacks are a lot easier to paint separately, then glue on afterwards.
You can see I kept the 'purity seals' pretty simple. I think they look silly, like ribbons from the state fair, but they are too much trouble to file off. So I leave them as white ribbons with red or blue seals, and I don't try to put any writing on them because I can't make it look decent. (It's good to know your limitations.)
Rik, Knight of the Flame
I gave his 'skirt' some highlighting with medium gray.
Here's a closer look at a shoulder pad with gold detailing by marker, and my simple purity seals.
The face is hard to see from any angle. I used flesh tone with brown ink wash, highlighted with more flesh tone. Didn't bother painting the eyes.
Pok, Purifier With Daemon Hammer
Wow, 'Daemon' and 'Mortis' legs on the guy with the Daemon Hammer – good planning or good luck?
My conversion work looked good at first, but the hammer shaft has gradually bent itself after final assembly. Whoops! Guess I should have bought that second box…
Koy, Purifier with Dual Falchions
The kit lets you get some nice action poses.
Sco Tee, Purifier with Dual Falchions
Can you tell I was running out of good arm options?
Che Kov, Standard Purifier
That's another squad done, now it's Chaos' turn!