venetian plaster?

[CJHorn]

A friend applied this stuff to a bathroom wall we're remodeling, and I understand another coat is needed. The catch is that we can't use the shower in that bathroom until a second coat and some final substance is applied. How hard is it to finish this myself? Note -- I'm not particularly handy around the house, but I'm willing to take a crack at it if it's not rocket science [and I suspect it's not]. Anyone?