I have a couple questions on cake making and really need some input.
1. what is the best way to get butter cream extremely smooth on the cake
2. I have tried to make fondant and when I roll it out to cover the cake it seems to get little cracks all over it? how can I avoid that?
3. what is any easy way to make a bow for the top of a cake?

thank you so much for any help.

Everything you need to know to make, decorate and assemble tiered/stacked/layer cakes:

http://www.cakecentral.com/cake-decorating-ftopict-605188-.html

Above super thread has popular CC recipes for crusting American buttercreams, several types of fondant and doctored cake mix (WASC and other flavor variations) and so much more!

The "more" includes (but is not limited to) smoothing b/c help and fondant help.

CC articles on How to Make a Bow cake topper:

http://cakecentral.com/articles/77/how-to-make-a-fondant-loop-bow

http://cakecentral.com/articles/128/how-to-make-a-gumpaste-bow

HTH