Start by removing the top cake, repeat for the middle cake.
1. Take the knife blade and insert it under the bottom of the top cake. If you feel the cake board you are in the right place, if not try again.
2. Push the knife in a little further and slowly move it all around the cake at this level. This will loosen the board from the cake it is resting on.
3. Get a clean plate or board. Now you are going to move the cake using the blade underneath.
This is also useful if you don't need to serve the whole cake at once.
By cutting the bottom tier each time, you are able to preserve the look of your cake just a little longer. I think it is worth the extra effort.