The paint is peeling in my bathroom. I would like to repaint it. I assume I scrape as much of the peeling paint off as I can before painting. Should I sand it smooth before painting? I have never painted a ceiling before, so any advice is welcome!
You'll need to scrape away all loose paint, and then skim those areas with good joint compound. Your best bet is to use a setting type compound which is less affected by moisture.
Then you'll need to seal and paint with paint suitable for wet areas. This is often an enamel type paint. Typical interior latex is likely to blister and peel again from the moisture.