I did my daughters bathroom and it was easy. Just get joint compound (it comes in buckets, premixed. About 5 gallons for a small room should do it, with some left over. Just smear it on the wall with a putty knife, and keep going over it, digging the knife in slightly, on an angle, and experiement. If you don't like how it's looking, you can scrape it off and start again
Let it dry a day or so, then paint
