Volunteering to gain experience
I don't think I could be where I am today with having worked voluntarily. Having no idea what to do with my life after university, and not wanting to spend my spare time doing a job that would get me nowhere in the end, I was eager to be able to get work experience at my university library. It was definitely a positive experience, and encouraged me that it was something I really could do. It gave me confidence, and helped we learn just what the job of librarian could mean, something you never really know until you experience it. Today I sometimes feel amazed that I now get paid for the job I do - having spent so long volunteering and never having had a (proper) paid job before it still seems surreal.
I spent my summer between third and fourth year doing this, plus volunteering at a local hospice and Durham's Botanic Gardens. Even though less relevant to becoming a librarian, I still think you can get a great deal out of doing something where you are meeting new people and trying something you haven't done before. Without all this experience I have no doubt that I would not be doing what I do now - having a decent degree is great but you need to have more! Since I've been in Cambridge I haven't done anything like I did that summer, and sometimes I think it would be a great idea. I can definitely see how it can fill gaps in your experience - the mention of teaching is something I have only observed, and I think some experience of that could only be a good thing. But now I am studying such a large amount of my time has disappeared, and what I have left I just want to do nothing and recuperate a bit! So maybe in a couple of years... I would love to do something involving children or maybe even just with a slightly different target group to most university libraries.