I have a question that there must be a simple answer to. When frosting small cakes, how do you keep them from moving. When I try to frost a 6 inch cake I have the hardest time because they start sliding across the turn table. I've tried putting some buttercream under it, and  some non slip materiel and it still moves. So what do you do?

What kind of butter cream are you using? I use SMBC and my 3" cakes are the only ones that move on me, but it's a really soft icing which has a lot of give. If you're using a thick powdered sugar icing, I don't know what to do really, maybe double sided tape? Melted chocolate to glue it to the turntable temporarily?

i use a damp paper towel under the cake board. this usually does the trick.

I use a non slip liner and haven't had issues. I have been making 6" cakes lately using ganache and there has been no slipping. What is your turntable made out of?

I have found that the thin rubber circles used for opening jars work great to stabilize the small cakes while I am icing them.  They seem to be more "grippy" than other non-slip materials I've tried.