When using hand files, it is best to hold the stock firmly in a vise or clamp. For better results, try to keep the stock being filed at about elbow height. For heavier filing work, the stock should be lower; if the work is finer, try to keep it up closer to eye level.
When you process wood in your shop, it is helpful to make notations on boards so you remember which have been cut to length or run through equipment like planers or jointers. Instead of using pencils for the notes, use chalk. Chalk lets you mark the wood without marring it so you can be more liberal with your notations. An inexpensive children’s sidewalk chalk set will provide several colors so that you can color-code your marking system.