As I was going along I knew I had to round out the top. So I said, if the RoboGnome wasn't going anywhere it might as well be used as a cookie jar. So I made it with a removeable top.
Take a strip of cardboard and make it fit inside the body tube. Staple it to form a ring. Draw a line around it after it has been pushed down enough to form the lip of your jar lid.
Take the ring and trace a cardboard circle. Make a bigger circle around it and cut it to look like a turbofan blade. Bend the tabs inward to form the gluing surface. Push this disk into your ring and glue in at the line to form the robot head platform.
Create a boxy form for the robot head. The height of the head should include the height of the rounded shoulder part. Create and glue on other details such as the eyes, earmuffs, 3 body buttons, and body slot. Start bending strips of cardboard to attach as the superstructure of the rounded shoulders. I like to fill in the voids with scrap cardboard for more support.
Make some forms for the gnome beard and pointy hat.