Does your ceiling look like this?
Improperly vented bathrooms
are notorious for flaking and
peeling ceilings. To stop further
damage install a bigger exhaust
fan or use the one you have
and let it run for 15 minutes
after taking a shower.
Tools you will need...
Putty knife, six inch trowel,
220 grit sandpaper or
drywall sponge
Joint compound.
The first step;
Scrape the area throughly
lifting and scrapping all the
lose paint free. Be sure to get it all, point the trowel on an angle and keep on going, alot more will come down as you go. When you are sure you have it all down, the area look like this.
Clean the exposed well with a sponge or cloth and allow to air dry..
Next is to open up the joint compound and mix it throughly.
Get it to a creamy texture.
Apply a thin coat of the joint compound across the whole exposed area and a few inches or so on to the painted areas surrounding it.
Don't try to work the joint compound to much, pretend your frosting a cake..
Once the area is covered you can run the trowel from one side to the other in smooth strokes with out stopping and with a light touch.
Once the area is dry, usually a day you can repeat the steps with the joint compound if necessary.. If not lightly sand it with 220 grit sand paper, or my favorite a drywall sanding sponge.
Once sanded wipe off the dust with a damp sponge, apply Primer and Paint.