You want to transfer your domain name to another registrar, possibly because they're cheaper or because they offer better service, or to consolidate all of your domain names with a single registrar.
Each registrar has a different transfer process. That process is usually initiated by the registrar you're transferring the domain name to, not the registrar you're transferring the domain name from. Check your registrar's web site for details.
Nearly all transfer processes will prompt you for the domain name to transfer, information about the administrative contact (and possibly other contacts), and billing information. The registrar you're transferring the domain name to will then send a form to the email address of the administrative contact for the domain name. The administrative contact will probably need to send the form to a particular email address to authorize the transfer and complete the process.
Make sure the email address of your domain name's administrative contact is up-to-date before initiating the transfer, or he won't receive the form the transferring registrar sends. (If you're not sure who the administrative contact is, you can use whois to find out, as described in Section 1.5.) If you need to change the administrative contact, you'll have to do that through your current registrar, not the registrar you're transferring to.
1.9.4 See Also
Recipes Section 1.5 and Section 1.6, for checking registration and registering a domain.
BIND Name Server Configuration
BIND Name Server Operations
Delegation and Registration
Interoperability and Upgrading
Resolvers and Programming
Logging and Troubleshooting