cferrero
Welcome to the treadhead world!
As far as tracks go there are many many many ways to get specific looks and everyone has there own way for the most part. Personally I start with a simple coat of flat black or dark brown. Then I have a canister of Iron Oxide pottery glaze that I apply to the tracks with a brush then polish them till it looks good. (This product makes the paint into more or less steel as it is finely ground rust) After this seal the powder with a coat of clear flat acrylic (I use Gunze brand) Wash the tracks with various shades of dark brown and tan oils. Add some mud to the tracks or leave them clean for a road marched vehicle. Last step is to take a soft pencil and highlight the guide horns and the contact surfaces of the tracks. Now obviously for tracks with rubber blocks you would only treat the steel like this, the rubber portion gets the same oil washes and mud just not the oxide or pencil. If your tank has been running on pavement drybrush the contact points of the treat with a slightly darker gray, but not black as these get scuffed pretty clean on pavement.
As for the decals, I undercoat with just Model master clear gloss acrylic....decal then overcoat with a mix of the Gunze flat and MM Clear gloss. I mix them about 60-40 heavy on the flat. I don't like to have a dead flat paint. Also right after decaling I like to go back and "fade" in the decals with a VERY light overspray of the base color.
I hope this helps a little ....like I said this is just my way..there are countless techniques. Just experiment a little.
Good luck on that MLRS
Kenneth
(Do have a special brush that is used for nothing else for this product, it stains the brush for life)