Question about setting tub in mortar bed

When packing the mud prior to dropping the tub in, how much of the mud should be packed and how much should be loose? I suspect while the mud consistency is the same as the shower dry pack, it need to have some give to accomodate the tub bottom inperfections and leveling.

What's the procedure here?

NM, I found the thread with the "piles" method described. I even posted in it

When I do it, which is seldom, I use bags of perfatape cement. I slit the bags so air can get in to harden it, then flatten the bags somewhat and set the tub onto them. THis way the cement cannot flow away, nor can it adhere to the tub's bottom.