To utilize this feature, you probably first will want a database with fields to pass the name, email address, subject and body of the emails being received.  Once you have these fields set up in a database, you should go to the Email Collecting link under Tools on the Database Overview screen.

On the initial Connection Info tab you can enter the server settings, determine whether the feature is turned on or not, and whether or not to leave a copy of the message on the server.  Then on the Processing Rules tab you can choose whether the email will create a new record, update an existing record, and/or generate a notification email sent to the address of your choosing.  You will find towards the bottom you can choose to map the from name, from address, subject, and body of the email into different fields in your database.  The Auto-reply tab will allow you to setup an email that will be sent to the from address on the email being collected.

After completing the process above, any emails sent to the corresponding email address will be delivered into your database.  Any attachments sent with the emails collected will automatically be downloaded and can be retrieved through the link in the history section for that record.