I am instaling corner shower with curved doors one front edge 1/4 in. 3/8 in center 1/4 in.at other corner. The floor is cermic tile, how do I fix a form for pour floor leveing compound, I wonder if using clay ( play dough) as a form in front, set base, make level remove and just pour concrete base leveler. Would work. Any other suggestion.

You would usually install the shower first but this is a retro fit. If you hot glue a piece of pine to the tile it should release... but I have never tried it. Let us know what you end up doing

Mark the edge of the shower on the tile floor, remove the tiles that will be under the shower. What is directly under this room, any joists or beam that is sagging?

I am not clear what you're doing. But it doesn't sound right to me.

Will there be any tiles on the walls? You didn't mention which method of waterproofing you'll be using for the floor & curb. The floor under the tiles is not supposed to be flat. If you use the traditional method, you need two slopes towards the drain. One under and one over the shower pan membrane. What are the walls substrate made of?

Jaz

While not 100% certain I have assumed he is installing a fiberglass enclosure or pan. You know what happens when we assume

You're probably right about it all being fiberglass. All I know is the OP was talking about the shower and in the next sentence said the floor is ceramic tiles. I assumed he meant the shower since the bath floor is not an issue. I to assumed.

Hey... are we charging by the word when people ask questions?

Jaz

I am instaling corner shower with curved doors one front edge 1/4 in. 3/8 in center 1/4 in.at other corner. The floor is cermic tile, how do I fix a form for pour floor leveing compound, I wonder if using clay ( play dough) as a form in front, set base, make level remove and just pour concrete base leveler. Would work. Any other suggestion. The shower base has a styrafoam support that goes on floor. An old house out of plumb and square, beams are good.
The front part of shower is curved and high in middle low on ends it would be hard to bend a board to curve. Maybe I can level shower put in hot glue to make a dam cut shower loose and then pour the floor leveler
Removing tiles too much work trying to find lazy way to do it.

Set shower base in place. Mark outline of front edge. Remove shower base. Build dam with plumbers putty. Remove small amount of putty from container and roll into ball between your palms until warm and soft. Then roll into string about 1/2 diameter and use to build dam. Pour floor leveling until just touches dam.