It is kinda complicate, and I just learn it in the class this week. Hope you can understand what I will say:
1. First make sure that you define the tables and relationship without error.
2. In the menu, choose database->generate. In the pop-up form, click the checkbox of "generate new database". Then click "Next"
3. Choose "Microsoft ACCESS" from the ComboBox of "installed Visio Driver". And click "New" by the "Data Source Name" text box.
4. In the pop-up window, choose "System Data Source", click "Next"
5. In the pop-up window, choose "Driver do microsoft access". Click "Next", and then click "finish"
6. Write a name to the "Data Source Name" as the name of ODBC, click "OK"
7. You will back to the "generate wizard" window. Click "next"
8. There will pop up a "Connect data source" form. You can ignore it and click "OK"
9. Then a familiar window will show and you can name you ACCESS database now.
10. Click "OK", then "next", You should know how to finish now.