Unlike undergraduate degrees, postgraduate degrees are not supported by government loans and often the use of personal finance is required. However, there are some alternative avenues to consider. First port of call should be the institution that you are applying to. Some institutions offer a range of bursaries and scholarships for students and so it's certainly worth looking into this. The criteria need not always be academic, so make sure to be thorough in your research.
Another approach to consider is finding a company, or getting your employer to sponsor your postgraduate study. In this regard it's extremely important to be able to explain the impact your degree may have on you as an individual and how this could relate to your performance at work. To be able to convince an organisation to financially invest in you, your reasoning must be detailed, clear, concise and most of all convincing.
If all else fails, you need to be fully prepared to cover the expense of your degree yourself, which re-emphasises the importance of being certain about this decision in the first place. Perhaps consider taking a year out to work, develop your professional and personal skills and then return to the question of a postgraduate degree when you are more financially capable. Or if you're thinking more short term, invest heavily in part-time jobs and internships and start budgeting now. It may not seem like much at the outset, but it will eventually add up.
Lastly and most importantly, be active in your decision making and flexible when you're weighing out your options. Think carefully about what and where you to study as this will affect the opportunities available to you. Don't just limit yourself nationally either, a degree outside of the UK might just fit your needs. Go above and beyond in your search for alternative sources of funding and start your planning as soon as you're positive about your decision to pursue postgraduate study.