I like to use a thick, flexible aluminium wire which is easily available in craft stores. First, bend the wire into a basic proportioned shape, winding the wire round itself to add strength. Allow a long end of wire at the base to stick the wireframe into a piece of foam.

Pose the wireframe in the desired position.

Wrap aluminium foil around the body to bulk it up as desired. You could just use gumpaste but aluminium foil is lighter.

Wrap gumpaste (or fondant fortified with tylose) around the limbs and torso. Try to place the joints in the paste towards the back or at places where they will be covered by other details later. You can use a little water and/or vegetable shortening to smooth out seams.

Continue adding the feet and the hands.

Add more details to the costume as required.

Shape the head from a ball of gumpaste or tylose fortified fondant, adding detail as required.

Attach the head to the body with water/edible glue.

Paint and add all the small details as required.

Allow the figurine to dry completely before transfering to cake. The extra lengths of wire coming out from the base of the feet can be dipped in coating chocolate and inserted into the cake. Hold in place with royal icing.

The Completed Cake: