When working with Plastimake it's often easier to make the individual components of an object separately. Each piece can be allowed to fully cool before joining them all together into the finished item.
Plastimake can be re-heated as many times as you like. The trick to joining two pieces of Plastimake is to melt a small section of each component until it has become transparent. When two warm, transparent pieces of Plastimake are combined they will fuse together to form a very strong bond.
The simplest way to join two parts is to dip a small section of each part into a bowl of hot water. Once the edges of both pieces are transparent and soft, press them together and you'll have a solid join.
Alternatively, a heat gun or hair dryer will quickly heat a section of Plastimake to the correct temperature. A cigarette lighter is another effective way to heat small sections of Plastimake, however be careful as it can leave black soot on your pristine white object!