Step 1. Gather Christmas Cards and a roll of tape.
Step 2. Find an empty door (our front door).
Step 3. Tape Cards onto door.
Step 4. Repeat when more cards arrive in mail.
As far as traditions go, apparently taping cards to the back of our front door is a tradition. Boy Wonder got the mail the other day and pointed out that we needed to start taping our cards to our door.