You can build the whole thing before painting; there are no sub-assemblies to paint first. The instructions provide a guide to the Buntfarbenanstrich (colorful) painting scheme (https://panzerworld.com/german-armor-camouflage for more information), but I kept to the plain (and very likely non-historical) panzergray for sentimental reasons – this is how I was used to the vehicle when I played it in World of Tanks. I painted it using Tamiya acrylics: panzer grey lightened with buff for the whole tank with zenithal highlight and some panel highlighting, used light grey to further highlight edges and smaller details, and then used oils (burned umber, raw umber, green, white) to “deepen” the color with filters.
Some streaking was added, some dust and some mud, and I declared the model done. I did not want to go overboard with rust, chips and scratches, as I figured the vehicle as a prototype had no time to actually get “used in”. It spent a couple of exciting days in the proving ground, and then went back to the machine shop to be dismantled. (Sadly.)
It was also an interesting experience with the AK weathering pencils: they are pretty good at making dust. The fact that the effect can be adjusted any time after drying is great.