To turn a sign into an elevator shift-left click with an enderpearl:
Another item can be configured
The signs first line will remain unchanged. It is the floor name.
The second line is always the same.
The third line is the target floor. First Line of that sign.
The last line shows in which direction the elevator will teleport and by how many blocks.
If you forget to set a floor name or want to change it afterwards
you can do this by renaming a piece of paper
and shift-left clicking it on an existing elevator sign.
Once you got 2 or more elevator signs in the same column use:
- shift-left click to change the target to the next floor up
- shift-right click to change the target to the next floor down
Finally you can right-click on the sign to teleport to the target floor.