I was going to do them in fondant, but I think I like the look of fluffy clouds vs. flat fondant ones.
i have done fluffy clouds using tip #12
I think it would depend how big you want them. If you're doing a 6" Carebear Cloud cake you might use a small round. A sheet cake you might just use a coupler.
My only suggestion is when you are making them with bc have a heavy hand. The lighter amount of pressure makes a flatter cloud. If you want a big puffy cloud use a heavy but not too heavy the bag breaks!
I read this on the Wilton site..........
Remove the tip and use only the coupler in the bag. This lets the icing come out in a poof like a cloud shape. Do three poofs in a group but let your artistic sense lead you.
I use anywhere from an 8 to a 12, depending on the size of cake and the design that I'm working on.
I agree I also use a #12 have fun!!!!