Most people will normally worry about job availabilities once they graduate (especially if you're in science), but this advice is mainly for education students. Do not worry AT ALL because from the placements you'll be doing during your undergraduate and maybe postgraduate if you continue, it will not be hard to find a job. If you still want to get experience elsewhere then volunteer on campus or wherever you want, but don't worry too much about buffing your resume when it'll actually be filled without you even realising.