If the tops of your cakes have risen unevenly, level them by removing the top crust with a long serrated knife.
To slice one cake into two layers, start by tracing a line around the middle of the cake with a long serrated knife. Then slowly rotate the cake while following that line with the knife and cut through the cake toward the center. After a few rotations you will have sliced the cake in two.
If you don’t get a straight cut, match the unevenly cut slices when assembling the cake, to prevent your finished cake from tilting.