1. edit your database using the editor.
2. press save as, choose a name for your edited files.
3. load up FM2010.
4. Choose a DB option and also check the box at the bottom that says change, next to 'load editor data files?'
5. you are taken to a new screen asking you to choose which of your edited data files are loaded into your current DB.
6. Load DB and start game.
You only need to choose which folder to save into if you have downloaded a custom DB