The Build:
Whether you're working with metal, resin, or plastic, the building and smoothing and painting methods are very similar. This is a pair of prints lifted from How to Paint Fantasy Miniatures by Andrea Press that I have in stock at the time of this writing. Shown here- using a standard #11 blade to defrag any flashing on the parts, filing smooth the areas to be joined, burnishing for the best finish painting later, drilling to run a wire through the heavier joints because we don't trust glue alone. Then apply putty to the glued joint and texture the putty to match the surrounding area.
The thing with drilling & pinning is not needed on plastic moulded kits, as the parts weigh very little, but on metal figures, and the larger resin figures, I think it's a real good idea. Resin or metal- use the CA type glues, I like Zap-a-Gap green label, but some modelers swear by epoxy instead because it deosn't get so crystalline hard, so it allows for temperature and humidity shift. On plastic moulded, the orange tube or liquid Testors is great, but many use Zap there too: