what is the best way to set up a otter toilet I was beaver trapping last season and found 5.

Me and Don Hightower from Texas was just discussing this very thing a dew days ago.
A flat set using a turtle shell with an attractant such as fish oil inside the shell should do the trick.
Otter are notorious for playing with turtle shells.. you have both the eye appeal and scent to draw the critter drawn over your choice of lightly bedded foothold trap, with enough swivels there’s no need fora drowner…but that choice is up to you.

If trying to trap them on land a simple dirthole set will do it.
But i would find a trail coming out of the water & drown them

Blind set 220's in pinch points
Dirt hole with red fox gland lure

By law I have to use a cage trap,,,,very simple and very effective

Series small holes with a couple different smells such as crawfish,mink musk etc.with foothold bedded under the holes.