if your using lancet thingie that came with alphatrak2, take clear cap off and freehand poking edge of ear. you get bigger drops that way because with cap on, needle barely touches skin and often doesn't touch it at all so you get no blood (took me a week to figure it wasn't i nor the cat's fault we were having hard time getting blood out of him when we had cap on). also on the weird occasions that we do get a tiny barely visible drop, i gently twist ear at area around poke site back and forth and that will bring out a bigger drop of blood without contaminating it.
also if you know you are doing things right, don't get frustrated about the little blood amounts or failed attempts, we all went through it but, after a couple weeks or so there will be more/bigger blood vessels in the ear you poke regularly and you will get a decent drop almost everytime. for now put a bright flashlight behind your cat's ear and you will see where the blood vessel area runs on your cat's ear, this will help you know the exact area to poke.