To gain access to your Teamtailor account, you will be invited by one of your colleagues. As you are invited, you will receive an email invitation. In the email click on the button Create account.
You will be asked to fill in your name, email and password. The email address used for your invitation will automatically be used, and will be the email you use to login. You can change this if you want.
If you already have an account at Teamtailor you have the option to login with that information and have all logins on the same email address.