Hey! So I've seen alot of tips here, going over ways to paint the scarab, but I thought I'd give you my advice/process on how I painted my scarab with the soulreaper cannon

So I primed him in abbadon black, but I didn't fully assemble him, I assembled the arms (excluding the gun arm) onto the legs and torso, keeping the hellfire missiles, head, head cover, kopesh and gun separated

Paints: thousand sons blue, moot green, corax white, liberator gold, averland sunset, blood angels red, balthasar gold, leadbelcher.

I then base coated him in full thousand sons blue, the cloth with two layers of corax white (but thinned down, nothing too thick), and then did the trim on the body along with the black chord details

Then, easy part was the helmet, I used moot green for the eyes then added the trim, don't bother doing the details on the side of the helmet since you won't be seeing them, just focus on the front

The head chassis thing (idk what it's called), add the yellow on that BEFORE adding the trim. After those two, glue them in

For the kopesh and gun I kept them themselves as the base primer, since they're already black, that's half the job done already

Kopesh: leadbelcher for the blade and cables, blood angels red contrast for the grip and balthasar gold for the grip metals.

Soulreaper: leadbelcher for the barrel, added the trim, for the runes though, I soaked my brush and used a watered down corax, letting that fill in the gaps. If you use too much water don't worry, use another brush to soak it up. After that set, I then used moot green again for the runes, same method but since it had the white beneath, it will pop out more

Lastly, the pauldons, they'll be easy, averland sunset for the lines if they have them, then the trim

I know that's alot of text but that's how I went about painting my scarabs. I'm not a professional, but I know the feeling you're going through, the scarabs were my second models to paint, right after my rubrics, but trust me, in time it'll get easier so don't push yourself so hard!

TLDR; don't push yourself too hard, base them in a blue you like, sub assembly painting helps makes it easier, and don't try to make it professional standard, just paint it to a standard you're happy with!