Registration is available for anyone who spent time at Royal Holloway College between 1965 and 1985. The main focus is on the 70's but there will be material that is relevant to alumni that were there throughout the period.
It doesn't matter if you didn't finish your course or graduate - it was the being there that counts.
You will need to provide some details about yourself - enough to identify you against the alumni lists. If you are not on the lists then registration may take longer and you will need to complete the alumni form on the formal Holloway site - there is a link in the Home section of this site.
Registation, even for those on the list can take a while as it's a manual process and the man has to be close to the lists at the time you chosse to register. But it should be worth the wait.