"To make a snowman" means to build a figure using snow. It involves rolling snow into balls to create the body and head, stacking them on top of each other, and adding decorations such as a carrot for the nose and buttons for eyes. Full definition
My snowman collection always takes me back to the excitement of making snowmen in the frosty cold Winter snow and the anticipation I felt during the whole month of December waiting for Santa Claus! (homeandgardeningwithliz.com)
December 29: Try tongue twisters, solve silly knock - knock jokes, sing, and act out songs about making snowmen, twirling like snowflakes, sledding down hills, and drinking hot cocoa at Winter Songfest (Boston) (bostonmamas.com)