What is the proper way to hold a file?

For right handed people hold the handle firmly in your right hand then leave you left hand open and place it on the end of the file (switch hands if left handed). When filing put your right hand down to the right and left hand up to the top left (as if looking at it top down) then place it on the bottom left of the material and drag it along to the top right of the material applying a bit of pressure with both hands onto the file in the process as you do the motion. . Make sure to use the entire length of the file to get a good finish