Frosting a cake isn't something you have to do every day, but it would be nice if it looked good when you did and not like something from Cake Wrecks. This tip from America's Test Kitchen uses a few items you probably already have to create a rotating platform for easy frosting.
The video above shows you how it works, but you'll need a mason jar and the insert from a cake pan. Flip over the cake pan insert and put it into the mason jar. The top of the insert is your new frosting platform, and it should fit snugly enough into the mason jar that it won't wobble. Then you can put the cake on the insert and turn it -- and the mason jar -- while you're frosting your cake. Simple and easy, as long as you have the mason jar and the cake pan.
If you don't have either in your home already, you could always go out and buy a cake stand, but they can get expensive and really only serve one purpose. There's something to be said for having the right tool for the job if you spend a lot of time on it. However, a cake pan and a mason jar probably wouldn't cost you as much and are definitely multitaskers.
Turn a Mason Jar into a Rotating Cake Stand [America's Test Kitchen]