Wait one. There are many different 'systems' used by turners to dry rough turned bowl blanks. It's kind of like witchcraft.
There are a number of variables that affect the rate of drying and chance of cracking. Important to me, as I live in an arid place, is the ambient humidity. Yours will be different than mine, or Reed's, or Doug's. Where will these be sitting while they dry? (Attics are hot and dry, basements are cool and wet. Shops are all over the place. Garages have a variable climate due to seasons, presence of heat or not.) What wood are we talking about? (Aspen, and mesquite from what I hear, move very little and are less likely to crack. Fruit wood cracks before the toppled tree hits the ground.) ETC.
I don't want to make this vastly more complicated than it needs to be. Talk with local turners in your area and see what methods work for them. Try some of those methods. Eventually, you will figure out what will work for you.
Personally, I coat the outside, but not the inside, of the roughed blank, put in a paper sack, and place on a wire rack (which allows air circulation), with the open end of the bowl down, in my basement where the temperature year round is most stable. Your mileage WILL vary.