Anon,
Depending on how intense your timetable is for third year, you could either try and attend some biology conferences, do an online training course (on a subject that interests you or on a topic that would help you develop more skills), or join a society which doesn't require you to attend every week but shows that you have other interests outside science.
You might also be able to volunteer to help at a charity for a couple of hours each week e.g. a food bank.
If all else fails, you could wait until you have completed your studies and then you could do something over the summer e.g. help with a project abroad.
Hope that helps,
Oluwatosin – 2nd year student – University of Huddersfield