The boots are the Witches Hat from the 'Boo to You' Framelits and the trim on the boots is the flame framelit from the Festive Fireside Framelits.
The sentiment is from the Cozy Christmas Stamp Set - ink the stamp directly with markers but don't ink the 'S' in 'yourself' - which gives 'you elf' :)
I then used the Envelope Punch Board to create a matching envelope, using Real Red card and the In-color Envelope lining paper.
Products used are listed at the bottom of the post :)