How to: take a trip to Dusseldorf, Germany on less than £150

A couple of weeks back, I was feeling very restless because I hadn't flown cross-country in a while, and so I went onto my #1 flight search engine site, Skyscanner, to book some cheap flights out to, well, literally anywhere. And weirdly enough, a little German town called Dusseldorf came up, offering flights for only £15 each each way, and I just couldn't refuse (despite not knowing a single thing about the town). Honestly, I thought it'd just be full of museums and art galleries - but it turned out to be so much more. Due to the fact that I'm still only 17, and this is the first international trip I'd taken without a family member, I had a strict budget to stick to - £150. Now I knew that this budget could be pretty difficult to stick to, with hotel rooms and food out, but I managed to do so, simply by asking around and figuring out how I could save the pennies. As it turns out, it's easy to get a 5* German experience.. if you know where to look.