The best way to test if all the merge fields and formatting of the email is perfect is to send it to a contact you create in the Contracts database.
Many email services let you create test email accounts - for example, Gmail allows you to use a plus sign in the name portion before the "@" symbol and add any text you like. If your Gmail address was "[email protected]", you could use "[email protected]" and "[email protected]" and both would be delivered to your "[email protected]" inbox.
Create those test contacts in the Contacts database and send the email to them. You can then see how the finished email will look with all the merge fields filled in.