To transform into vehicle add on mode, fold the arms down to the sides, swing them back 180 degrees so they point upwards and then fold out to the sides to form one long wing blade over the front of the chest. Fold each leg out to the sides, probably popping off it's ball joint in the process, then bend the knee & ankle to form a claw. Peg onto the front of Heavytread's tank mode to form a device similar to the mine clearer found on the front of this Assault Breacher Vehicle. It's one of the more integrated Minicon/Vehicle combinations in Power Core.
From here fold the wing halves up and the legs down to form his armour mode. It's one of the better ones covering a large area of the robot's chest.
From there bring the legs together, still bent, and fold the wing tips back to form a claw weapon capable of being held by Heavytread or plugged into the underside of his right arm.
No two ways of saying this, it's a poor Minicon even before the legs fall off if you even look at it wrong.