My first in olive drab
giving some thought about fit, I usually add 1" to the exact wrist measurement. for everyone making their own, this is a good rule of thumb.
I decided to now leave 1/8" extra in the loop and the attach cord for the button. this allows a "looser fit" to start; but if the wearer desires more snug, a bit of the loop can be pulled out (pull the end with the steel), then the end can be snipped and burned again at the steel (of course you can't go back after).