I'm a newby to using thin set I have been told it's simple but I need some directions or step by step walk through to ensure that the job is done correctly from beginning to end, can anyone help me.
Hoping you are referring to a mortarbed, and not actually thinset. A mortarbed is to lend support to the base/bottom of a tub or shower unit made of materials other than metal. These materials can often flex if not properly supported. This can cause cracking or breaking the seal around the unit. I use a 5 gallon bucket of premixed mortar. I measure how far the bottom of the tub/shower is (going to be) from the floor. Lay a sheet of plastic down to prevent the moisture from the mortar from ruining the flooring or subfloor material. Pour the mortar about 1/2" higher than the measurement from floor to tub/shower. If the unit has some bracing already built into it, pour between these supports. When you set the unit into the mortarbed, make sure you compress it into the mortar. You will now have a solid surface under the unit.
If you have never made a mistake, you haven't done much.