I don’t know of the location where most of these are done, but i asked around for you and Mateo Way said
“I would visit one of the HTC Studios in Tempe or Phoenix and ask for Dana or Kevin. Both have done scarification work and if they are comfortable with the project may be a good source to someone who is”
Here’s an online guide to scarification aftercare, but to sum up the answer to your question:
You want to keep it dry so that it will scab over and scar properly, so leave it uncovered. Large scarifications and also ones in high movement areas may need to be moistened during the day to prevent uneven scarring due to the scabs being too big/moving too much.
In my experience i’ve seen people wear medical gauze and an ace bandage for a couple of hours after but that’s about it.