To set up your account to work with Google Apps, you will first need to set up a Google Apps account.
Once you have the account created, you will need to get the mx entries set to the google servers. To do so, you will use the DNS Zone Editor tool in the cpanel under the domains section.
In this area, select your domain from the drop-down menu. You will see an area to add an entry and below that is an area to edit existing entries.
Add the following entries:
For each entry, set the name value as @, the priority as the number, and the destination as the entry itself.
It will look like this when you finish:
Once those have been added you will need to delete the existing mx entry for the domain. By default it is 0 yourdomain.com.
To be able to access the google apps by using mail.yourdomain.com, you will need to change the cname for the domain using the DNS Zone Editor tool in the cpanel.
Click on edit. Where it says Host: type in “mail”. Where it says Points to, type in “ghs.google.com” without the quotations. And click Save.