Made a 2 layer 12"x18" sheet cake, when I went to put 2nd layer on top of 1st, the cake started breaking. Can someone please share with me an easy way to do this without the cake falling apart? Thanks

I use a cake board and put one end of the top layer on top of the bottom layer and ease the board out the other end little by little. I hope this makes sense. I'm sure someone will have a better explanation.

I cut my sheets in half (so they are basically quarter-sheets) and place them side by side. The seam in the middle seals up with buttercream and the smaller cakes are much less likely to break.

I do the same as AnotherCreation and VentureSister, but I bought a giant sideless cookie sheet just for this purpose. I spray it lightly with non-stick spray, then wipe most of that off, to reduce the icky taste. The I just put the sheet cake layer on it and gently slide it off onto the bottom layer.

I've used Bethkay's tip in the past too.

I have two Wilton cake lifters and love them, but generally just end up using one with my hand supporting the other side of the sheet cake. I match up the 2nd tier on one side and lightly drop it while removing my hand, then just carefully slip out the cake lifter for the other side - Voila!