I think the fact of the matter is that it takes hard work, and a lot of blood, sweat and tears. I'd also say that you need a bit of luck, good timing, and some sacrifices.
Working hard is the name of the game, and I also worked as a lorry driver for some period of time to part-fund an integrated course at a top school, which I start in a few weeks. It was long hours, probably between 60 and 70 hours per week, meant being away from home all week, and took it's toll on family life and hobbies, but at the end of the week, I had around £550 in my bank account. In my opinion, a big thing to remember is to keep your eyes on the prize, and keep your goals in sight. Hard work feels much easier when you keep your eyes on your target.
A big help is cutting-out those obvious big spends, such as pointless gadgets, and unnecessary holidays. Everyone needs a phone, computer, possibly an iPad, especially if it comes in handy for training, but it's cutting-out those silly things that are important. If I wanted a drink, I'd have a few cans of beer at home, not spend £100 on a night-out with the lads, bearing in mind that £100 could probably feed me for three weeks, given my simple tastes. Think about whether you genuinely need something, and if you need something expensive, think about it's longevity, and re-sale value.
My decision also cost me my girlfriend of two years, after she became frustrated with me working such long hours, to fund a course that would mean me being away from her for 18 months. I admit we had our problems, but this pushed her over the edge.
The bottom line is unless you have parents, and or grandparents willing to help you out, the only option is to get out there and earn as much as you can, which sounds like what you're doing. Everyone has a different financial position, so each to their own, and take it at your own pace.