kitbash

on this link to a kitbash using armada prime what parst or materials do you use to make the body parts, e.g. in vehicle mode the curves such like the front. do you use putty or something?
reason im asking becuase ive got the leader version of armada prime liying around and some other tfs which i would like to experiment on
plus if you can give some tip, materials and best paint plus the best transformers you think is the best to modify for yourself?
reason im asking becuase ive got the leader version of armada prime liying around and some other tfs which i would like to experiment on
plus if you can give some tip, materials and best paint plus the best transformers you think is the best to modify for yourself?