I know it may be a bit early for a tip like this, but the tips I’m going to give will work with any holiday.
Step one is to find accessories for your pet that you feel fairly certain the pet will tolerate. Here I chose two different collars, one was jingle bells and the other looks like a wreath.
Second get one of your pet’s favorite treats to place them where you’d like them and get them to look where you’d like. In this case, we used hard boiled eggs. Tawny loves eggs of any type and recognizes the word too, just like me. You will need a handler to help you with this. I actually used two, one to get the dog where I needed her and the other to aim the light.
Speaking of the light, I used a speedlight in a Lastolite softbox. Try to place it as close to the pet as possible for maximum softness to the light.
Third, place the pet so that there are some holiday specific items in front of and/or behind the pet. I usually have these items slightly out of focus, but still recognizable. Balance the flash exposure with the ambient such that you can see the holiday items, but the focus is on the pet.
Finally, in post processing, process like you would most portraits. Make sure to use a vignette to further emphasize the pet.