From talking with owners on the PetDiabetes mailing list, ear pricks are generally not used on dogs. However, Leo was successful in using this method for on Duffy, a diabetic Schnauzer he fostered.  Since it worked for them, this method might be an option for you and your dog.  

Schnauzers are groomed so the hair inside the ear is very short. I kept it completely pulled off Duffy so the blood pools easier and doesn't get spread through hair. This doesn't bother dogs; the majority of the ear seems not to feel pain. Only the cartilage where the flap is seems to feel pain. For other dogs I would keep the insides of the ear shaved completely, and pull out the hairs as it grows. I think it would work on any breed if the hair on the inside is kept short or removed and if the ear is large enough to squeeze out a drop of blood. Dogs with cropped ears might have trouble with this method since usually only the cartilage part is left behind and that hurts when injured.

Duffy and I had a routine. I fed him, then let him out. I got the glucometer, inserted the strip, opened the lancet and got it ready, and had out a piece of wet paper towel. I sat down and called him. He comes every time he's called.

I picked him up and cuddled/kissed/snuggled for a minute or so. Then I had him lie down on my lap. I would turn him so the ear I was going to prick was away from me, the inside of the ear facing away. I alternated ears.

When it's hot there's plenty of blood in his ears and the inside is pink. In the winter his ears are white and cold. When they're cold, I compress an ear VERY tightly, held flat between my hands, for 30 seconds, then let the blood flow, and keep alternating until the ears are pink. I don't have to do this in the summer.

I'm right handed. For lefties, just change right for left below.

Then I held the ear clamped at the base between my left thumb and the side of my left palm and index finger. I did this until the ear was very pink with pooled blood. If you squeeze too hard you stop the inflow of blood too, but that wasn't too much of a problem.

I would then slide the clamped hand toward the tip and the blood would be squeezed up the ear. The ear would be lying on my left thumb. When the ear was good and pink I would take the lancet in my right hand and prick him with the lancet, but only about halfway the length of the lancet. I did it slowly and carefully, which he didn't seem to mind. Lancets are longer than dog's ears are thick and if you just jab it goes through. I pricked against my thumb so I would know not to go too deep.

I found it best to prick at least 1/2 inch from any edge of the ear. There was more blood there.

Then I would carefully set down the lancet, take my right hand, hold the tip of his ear, and press the ear down against the left thumb. This usually squeezed out enough blood.

If it didn't, I would reposition, let go of the ear, and fold it in half, so the tip and the base were together, the middle of the ear folded, and the inside of the ear with the prick facing out. Then I would use both thumbs on one side and both index fingers on the other, and squeeze blood from the base and tip of the ear to the center. This would almost always work.

On rare occasions I'd have to stick him twice.

I had a glucometer that needed a relatively large drop of blood, but this wasn't a problem. I can't remember the name because we gave it to Duffy's new forever-family. 

I always looked on the other side of his ear for a blood spot in case I went too deep. Then I used the piece of wet paper towel to wipe off any remaining blood, and I held pressure on the prick for about 20 seconds.

While waiting for the glucometer to register I cuddled him some more.

Duffy didn't mind any of this at all. It almost seemed like it didn't hurt him at all. Everybody who saw me do it was amazed that he didn't even react.

--Contributed by Leo and Duffy