“Smush is a 3 year old Jack Russell Terrier and Red Miniature Pinscher mix. You might notice that in the video I call him “Smu” — just a nickname. Amazingly, I shot this video the same night that I taught him this trick. He's an incredibly smart dog that seems to have the ability to pick up new tricks very quickly, sometimes in a matter of minutes.
If you're wondering how I taught him this trick, the first step is to make sure your dog knows how to respond to the ‘touch' command where he will use his paws or nose to touch your hand or other object. Once you have that down, you leverage that and apply it another object, in this case a door. Use a clicker and reward with small treats. Since Smush is a smaller dog, I take small treats and break them up in to even smaller pieces to extend the training without overfeeding.” – naoki1978