I dread square cakes...never seem to have any luck with making perfect corners. Have researched and looked at tutorials/information but still having trouble. Luckily a lot of my cakes are requested to be round (my fav) but can't seem to be happy with anything that is square. I don't have any probs with sheet cakes...any thoughts or suggestions would be greatly appreciated. Thank you!!!

Are talking fondant or buttercream?

oh...buttercream...sorry!

There is a really neat tutorial on CC about frosting a cake upside down makes a super smooth finish. It is done on a round cake but I think a square cake would work too. Go to "articles" then go to "cake techniques"
There is also a tutorial on youtube done with spatulas and scrapers.

How do you get your sheet cake corners square? I would think whatever you do to one would work for the other.

here are pics on how I do it: http://cakecentral.com/cake-decorating-ftopicp-5396443-.html

Also a common mistake (that took me years to overcome!) is that we dont HAVE to ice to the shape of the cake. If the corner is droopy, then build up the icing on the corner to get it high enough and then square it off.

thank you for the tips...have done some of them already but i will continue to plug through with it!

I feel your pain. I've watched Sharon Zambito's videos and other too who make it look so easy. This is the first time I've seen Indydeb's pictures so I will try that next time. On my most recent cake, I thought about houses that I've seen with clear plastic bumpers on corners of open doorways so I decided to use some stiffened buttercream left over from building the dam for the filling. I put some of it on the corners and then did a crumb coat because the cake was a moist chocolate cake. Then, when I was ready to apply the final coat of buttercream, I already had some frosting on the corner and didn't feel as intimidated about using the bench scraper. It sure seemed to work better for me, though there is still room for improvement. Hope you understand that explanation. The cake is a 3D train atop a sheet cake and I have it posted in my pictures. Thanks for the post as I am excited to try the method shown in the pictures next time.