1. Go to http://www.google.com/a and click on the Get Started button.
2. Choose the Standard Edition which is free.  Note: You can choose the premium if you would like.  It provides more storage space and 24/7 tech support, but costs.
3. Type in your domain name  without the http:// or the www. Example: If your domain was http://www.yourdomain.com, you would type in yourdomain.com.
4. Click the Use my domain button.
5. Choose how many email accounts you would like.  If you don't know right off hand, choose 100.
6. Fill out the form about you and your company/organization.
7. Set up the administrator account by choosing a email username and password.
8. Click the I accept, Continue With Setup button.
9. Click Create New User.
10. Fill in the first and last name of your user, and choose an email address for them by typing what is in front of the @ symbol.
11. Click Create My User.  To add more users click the Create Another User link.  Continue this until all of your users are setup.
12. You can use Google Mail for Apps with Outlook and Outlook express.  For information see the help guide here.
13. To make your new mail live you will need to change your MX records.  For information changing your MX records see the help guide here.  If you need further assistance with this please send an email to support@publishpath.com.  They will be able to assist you.  Make sure you have your username and password of the place you purchased your domain from. 

Blackberry Users: For information on setting it up on a Blackberry view the help guide here.