You should start out with a recipe that suitable for carving. A straight box mix and some cake recipes are NOT suitable for carving. The "Durable 3-D Wedding Cake" recipe found on this site in the most saved recipes is the one that I use. I used it for my Dr. Suess cake that's in my photos.

I bake, level and fill my cakes then put them in the freezer until they're really cold but not frozen. (This isn't necessary but I find that it makes it easier for me to work with the cake when it's cold). I carve it and I like to wait for it to come to room tempature before crumbcoating because I have a problem with my icing crusting if I don't. I don't ever ice a frozen cake. Some do but I don't have the best results doing it that way. I don't know if you're covering with fondant but you never put fondant on a frozen cake.