DIY in this case stands for Decorate It Yourself! We don't have a mantle but we do have a piano and the top of it is almost like a mantle. The concept is similar so bear with me and I'll share with you how I decorated my not mantle for Christmas this year!
Christmas tree: Made by gluing gold ribbon to paper
Baby It's Cold outside: Diary of A Mad Crafter
Ho Ho Ho: The Social Home
Glory to the Newborn King: Happy Looks Good on You
Deer: kind of inspired by The Social Home but I actually made this last year
Mini Christmas Trees: Fynes Designs