Posted By arkie6 on 15 Aug 2016 06:45 AM
Posted By ronmar on 14 Aug 2016 11:34 PM
It might be easier to block out the area for the shower a little deeper than necessary with a wooden form and build-up/grout in the shower later to the desired height.
That is what I would recommend as well.
Me too, it's done with a damp mixture of portland/ sand - dry packed and shaped with trowel