For newcomers to ski edge filing, knowing the type of file to use is an important first step. Mill files are the traditional file of choice for edge filing. Steel mill files from six to eight inches are a relatively low cost and are best for side edge filing. If you are filing base edges, you should look to go a little larger, up to ten inches. You can go even longer still if you need to file fat skis or snowboards. Hand ski edge filing is something that takes a lot of practice to master.
For newcomers, try to get a routine worked out on an old ski. Steel files can do a lot of damage if not used correctly, so here is a great tip. Find a used or broken ski from a second hand store. Use this ski to hone your ski edge filing skills. Practice makes perfect, so don't threaten your skis without getting the right amount of practice at ski edge filing before trying it on your main set.