I need to make a cake that looks like the Mickey mouse clubhouse hot air balloon. The lady wants the bottom diameter of the bucket part to be 12" round. I am thinking that the height will be about 10". So with a cake that size, what is the best way to cover it?

My suggestion would be to cut a circle the size of the top and then to cut a rectangle that measures the height of the cake on one side and the diameter of the cake (plus a little extra) on the other. Sprinkle a little cornstarch on the rectangle once it's cut and roll it up along the long side. Crumb-coat the sides of your cake and unroll the fondant as you go around the side, smoothing as you go. When this is done, smooth the seam between the top and sides of the cake with a little shortening. Rub a little shortening on the sides to absorb the excess cornstarch. This is basically Sharon Zambito's version of how to do this, and I find it works very well.

You can use a strip of bakers parchment to cut the side fondant to a little longer than you need. Roll this up with the fondant, it helps to keep the roll from sticking to itself.

That sounds like a good idea. Thank you. However, do you think there is a chance that the fondant will sag? What do you think about covering it in two pieces? Draping one half over the front and the other over the back and having seams on each side?

If you hold the fondant roll close to the cake, you use the roll itself to smooth the fondant against the cake. Take a piece and practise against a tall cookie tin, you will see.

If the bottom of the bucket, diameter is 12" will there be a top diameter. if the top ( is just a circle) is around 14". cant you turn it upside down and cover it with fondant, like covering any other cake? Thats if its just a bucket shape? Hope its not a silly idea.

Iren yr idea is great too.

That's not a silly idea at all! Actually pretty smart. I think I will allow myself plenty of time to try both ways if need be. Thank you everyone!

I would recommend cover the top, then the sides, as Marianna has suggested. I covered a double barrel cake that was 8" wide and about 12" tall, and my problem was that the fondant kept tearing. I ended up leaving it, covering the sides AGAIN using Marianna's method, then covered my seam with a detail (it was a bird cage). By all means, try multiple methods, but this was the best way for me.
Good luck!

Covering this size and height of cake with fondant in one piece means that the bottom is so rippled that you would waste a good hour trying to get it smooth. Doing it in 2 pieces takes 10 minutes tops.

AThanks for sharing

There shouldn't be any ripples.  

Make a wax paper template of the side of the cake.  Roll your fondant onto wax paper template.  Trim the fondant and lift the wax paper against the side of the cake.  You will have one seam in the back that can be made to look like a seam in the plastic bucket. Then put a band around the top of the fondant sidewall, and place the cover on the top of the cake.  Are you doing the characters also?