OfficeTalk lets you create hierarchical folders enabling you to structure the way in which you store mail. For example, you may create a folder called Personal Mail which is to be the root folder for all your personal mail. Under this folder you may wish to create a folder representing each person that sends you personal mail. You may wish the structure to look similar to the picture below:
The folders representing each of the personal contacts are sub folders of the 'Personal' folder. To create a sub folder, simply drag an existing folder and drop it onto another folder. The folder that you drag will become a sub folder of the receiving folder.