All you need is to know where the cut is going to be, and a heavy sturdy knife or a needle nose pliers. I find it really easy to work with. I love to get me some black egg crate but cannot get any locally. MO is too expensive, so I use the white ones from hardware stores.1 side down, now to do the other side and the base then I’m almost done.
I forgot how hard it is to chop through egg crate. The things we do for wrasses hey.