We remove ours by ourselves. As a retired veterinarian I've had some practice. I have also seen some done very badly.
I do ours at 3 days of age. By that time you can tell the pups are nursing well and gaining weight and this will not be a huge stressor. Plus their neural network is not completely formed until a few days later. I'd get them done by no later than 5 days.
Clean around the dewclaw with disinfectant scrub or soap. If you are using alcohol you must let it dry to kill mircoorganisms.
Using a straight mosquito forceps, some folks call it a hemostat, some call it a Kelly clamp, the mosquito is just the smallest of the bunch; here's a link for one on Amazon.com
http://www.amazon.com/Halstead-Mosquito ... B000BJUG0E. I place it against the skin in the space you can feel between the end of the dewclaw bone and the bone of the paw. You should only need to clamp so you are involving no more than 1/2 inch of skin.
Closing the clamp pushes the dewclaw away and compresses the skin. Make sure you have clamped so that no part of the dewclaw is trapped; it must be all pushed away.
I then use a scapel to cut, using the forceps as a guide. Slice through on the side that is nearest to the dewclaw.
If the incision is oozing a lot of blood, more than a couple drops, I'll use a silver nitrate stick like you use for toe nail clips to cauterize. In the pups I've done that to it's never shown up later. It's such a small incision and the hair grows and covers anything there.
Mom will lick at them so just watch to make sure it is healing ok. It's a couple less nails to clip, less to catch on something and tear and less nails to possibly split.
Hope this is making sense. Let me know if I can explain more.