I used a scrap piece of 1/4" aluminium to create a sort of template - it has a curve at the radius to form the lip of the lid.
The 1mm aluminium sheet was attached to the template by a screw thru the centre, so it could be rotated about the template. Then the lid + template were clamped to the bench and the lip formed by gently hitting with a small lump hammer against a blunt cold chisel. The best technique to avoid warping the lid is to go around the circumference several times, each time making the lip just a little deeper. A vise was used to square off the lip edge and finally excess material was filed off the edge.
Roger is right about the handle - it was left over from an early stove project.