To make this easier to understand I have uploaded some pics for you. The dowels determine the depth of the cake, so buy the size you want, e.g. 1″, 1.25″ etc from your local hardware store, and cut to usable sizes.
Dowels ready to use:
Cakes lined up ready to level

knive horizontal to work surface ready to cut:
Cut across, use hand to steady and hold cake if necessary
Cut cake, is it level?
Yes, it is.
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