Designing Kitchens and Bathrooms - How to put a mortar slope in a flat pan?

My plumber installed a copper drain pan for my shower over my existing ceramic floor. (We are putting a shower in a nook in our washroom.) The copper pan is 3ftx4ftx6in. They said to put some mortar mix in a couple of inches deep and make a slope with it. Any ideas on how to trial the mortar mix into a slope to the drain in the center? My drain is adjustable (screws up or down) from half inch to 3 inches. Also, should the copper pan be treated with anything. I am ceramic tileing over this bed and walls. thanks for any input. This is my plumbers first experience with this as well.

I'm not a fan of this copper pan method. A properly constructed shower has a preslope mud bed, then a pan liner over the preslope, and then a final mud bed over the pan liner. The idea is that water that gets through the final mud bed and makes its way to the pan liner will make its way to the weep holes in the drain because the pan liner is pitched to the drain. The copper pan is flat, and any water getting through the mud bed may or may not make its way to the weep holes. After a while the smelly dirty water that doesnt make it to the weep holes makes the shower smell like a swamp.

Paste this link into your browser to see how a shower should be constructed.

http://www.ontariotile.com/preslope.html

You may also want to check out www.johnbridge.com. He has a great site with lots of good information on shower construction and very helpful forums.