Of course the size of the butt section of your leader depends on your rod size.
For a 10wt, I would use 5' of 40# hard mason. Then loop it to 3' of 16# hard mason (using a bimini twist to double the loop on the 16#). Then finally use 1' of 60# - 80# flurocarbon shock, attached to the 16# with a double blood knot.
The above is the same IGFA formula I use for the world record giant tarpon we fish for at Homosassa each May - June.