A lot of people use the Minnesota protocol developed by U of Minn's CF clinic. https://chw.org/-/media/publication-media-library/2017/08/09/19/04/1245en.pdf My kid does 3 vest treatments a day for 30 minutes. Pressure at 10 with 5 minutes each starting at 10 hz, 12, 14, 16, 18, 20. If he gets sick we increase the number of treatments by one or two.