I made a start on the helmet: I used some 1” wide masking tape to mark the two sides of the ridge – I just applied the tape over the area I wanted to keep and made sure it was securely stuck down. I next used a Dremel to cut the sides down using the edges of the tape as a guide and then pared away the waste with a sharp chisel. The ridge was sharpened by filing away at the line I wanted and then adding some Milliput to slightly soften the edge again. I also chiselled away the brow are of the helmet. I did this by eye using Empire Strikes Back screen grabs as a reference.