How hard is it to cover square cakes with fondant? Any tips?

I'm preparing for my first 4-tiered square wedding cake covered in fondant. I've only used fondant for round cakes and have had pretty good success. Am a little nervous about the squared edges.

TIA!

My squares still need a lot of work but there is a video here that may be helpful to you, Nati has a lot of great information on her website

http://www.how2cakes.com/squarecake.html

Here is another great video from aine2 on covering a sqaure cake in fondant.