I was wondering if someone could help me and tell me what I did wrong. I put the fondant on my cake and when I went back to look at it a little while later it was bubbled out at the side, like there was an air pocket under the fondant and it tore the fondant a little bit. I am not sure what happened and what I did wrong. Any help would be great please

how long after baking and cooling the cake did you ice and fondant the cake? it might not have settled yet

I baked the cake and then iced and put the fondant on the next day

You probably didn't do anything wrong. Sometimes a change in temperature can make the bubbles appear under the fondant. If you give the cake a chance to settle is does make them less likely. Sounds like you already did that. Just poke the bubble with a pin or something similar and work the air out. You can probably smooth out the small hole in the fondant or patch it with BC of the same color. HTH

if you need to patch it up, sometimes i melt a little fondant w/ some water in the microwave, then brush in the paste to fill in the holes.

I did patch where the bubble was but then I got 2 more in different spots, I will post a picture tomorrow of the finished cake, It is a Nemo cake for my son's birthday. This cake is driving me nuts, I just don't understand why I keep getting more bubbles.

How much butter cream should I be using under the fondant? Maybe I used to much, could that be what happened? Also When I am rolling out the fondant do I use flour or icing sugar under it or can I use either of them. Sorry for the questions I am just trying to figure out my mistake because I am making a wedding cake at the beginning of June and it is a 3 tier cake, so I am getting very nervous now about doing it.

corn starch i found works the best!