Unpaid work and volunteering, if wanting to build experience and develop skills in specific areas, is a valuable tool at your disposal. The benefits that you receive from offering your time, even for free, are vast - it will boost your CV, provide you with 'real world' examples for answering application criteria and interview questions, and shows an employer you are keen to develop yourself. It might also open up doors to opportunities you didn't know existed, or to ones that you might not have had the experience to apply for before volunteering.
Unpaid work and volunteering can range from working for organisations through work experience, in charitable organisations or even independently by contributing to a good cause, such as tidying up your local environment.
Providing extra support for charities in their shops, warehouses or fundraising events are worthy causes with big experience gains for you.
There is nothing stopping you from picking a good cause of your own and volunteering to make the world a better place.
Internships offer longer periods of experience working with employers, often in industry specific areas related to your degree.