I think that's a tough one just because each of us are different. My rheumatologist was super helpful and gave me scripts of prednisone in 20, 10, 5, 2.5 and 1mg. When I was struggling around 5mg he shared with me one of his patients took over a year at 1mg to taper off. My first time with PMR I spent the last six months tapering between 1mg and 1/2mg until I could finally stop taking it and my morning pain was minimal - less than 1 on my scale but still a little achy until I got up and started moving around. If I remember correctly my first time I tried tapering every 2 weeks and it sometimes stretched to 3 weeks to a month to switch to my next lower dose. I also had a few times where I had to increase the dose but when I did that I didn't go all the way back to the previous dose. Instead I bumped it back up to half of what I tapered down so that I still was making progress with the tapering.

Some folks have had good luck with a super slow tapering plan:
-- Dead slow and nearly stop reduction plan (DSNS - Tapering)
https://healthunlocked.com/pmrgcauk/posts/131189593/dead-slow-and-nearly-stop-reduction-plan

Like many others I’m figuring it out on my own with the help my rheumatologist. I started on 15 mg, then went to 12.5 mg and then 10 mg, each about two weeks apart. Now I’m reducing 1 mg every two weeks.I had the same problem when I went from 12.5 mg to 10 mg, and had to increase it to 11 mg for a week because I had a lot of pain and stiffness. So far in my experience over the last several months when I lower my dose, I get some pain. It lasts several days, and I would say the pain is sometimes a 4 out of 10. But then it all stabilizes and I spend another 10 days or so at that dose and decrease again. So far it’s going well and the advice for my rheumatologist was she didn’t want me to stay too long at one dose. She is supportive of what I’m doing..