Before assembly, check for accuracy and remove release agent with isopropyl alcohol, degreaser, or acetone. Cut off sprues with a saw/cutter. Wear a dust mask or respirator during mechanical processing to avoid inhaling dust particles.
Carefully heat warped parts (e.g., with a hairdryer) and bend them into shape. Glue with 2K or superglue. Unpainted castings will darken over time and may yellow, especially when exposed to UV light.