Once you have an account created, you can login by going to this address:
https://collabornation.net/login/yoursitename
Please replace yoursitename with your site's unique address.
If you have forgotten the URL then you can also go to https://collabornation.net/login to log in to your account. Once logged in you will automatically be taken into your organization's site.
If you haven't created an account yet please read the Registering a new account article to learn how.