You can just add another administrator account to your domain. The steps are stated below:
1. Open your web browser.
2. Go to http://domains.live.com.
3. Sign in with the Live ID you wish to make an administrator.
4. Click on Get Started.
5. Enter the domain name you wish to add to.
6. Choose whether to include hotmail service or no mail.
7. Click on I Accept.
8. You will receive a new MX record or a new CNAME record depending on which mail service you chose.
9. Set the CNAME record or Add the new MX record to activate the new administrator.
