What I did was start out small 10-15mins and a pressure that wasn't painful at all and just under the point of being uncomfortable and increasing the time until I built up the tolerance so, 15mins became 30mins, then 30mins twice a day, then 45mins twice a day and then a hour twice a day. Slowly I increased the pressure as my tolerance for the pressure I could handle continued to increase I'm just a little under -5 now and I don't really want to go higher. I hope this helps