MUST READ BEFORE TRANSFERRING
There's two things that must be setup correctly on your domain or the transfer will fail. You must check these 2 things before trying to do a transfer.
1. You must check to make sure if the email on your domain is correct. Once you start the transfer it is going to email this address asking for permission to move the domain. If the email listed isn't your email or doesn't work you can't respond to this email thus the transfer will fail.
2. You must make sure the domain isn't locked. If it is locked even if you agree to the transfer it's going to fail.
You can check both of the above by going to www.whois.sc once here type your domain.com in the field and click submit. Find where it says "Administrative Contact:" This is where your correct email must be listed. Now scroll down to where it says "Status:" if the status says locked you must get this changed before doing the transfer.
To get the above changed you must contact the registar you bought the domain from to do it for you. (some let you make the changes yourself from their control panel)
Note: You can't transfer a domain unless it has been at the current registar for at least 60 days. If your domain is expired you cannot transfer it until you first renew it with the current registar.