I actually think "saving" is a waste of time and quite idiotic these days, with interest rates so low and the inflation so high that negates any benefits that you might as well simply just spend what you have and enjoy it.
People constantly say you should "put away for a rainy day" but much better is to spend money to make money, any fool can put £10 under the mattress but in 10 years it will still be there...
If you are dead set against spending though I would start to think of ways to make it hard for yourself to spend money, like going to an amusement park or three and converting it all to 2p pieces so that you will be to embarrassed to spend it anywhere.
Just try it one time, convert £5-25 into some really small change every week and see how it starts to pile up really fast ;)
By the way, mutual funds are really bad to invest in, and they ARE NOT SAFE. As soon a there is any kind of dip in the stock market you will find your fund taking a massive hit and if you try to get it out early you will be penalised harshly. They only ever perform well in a bullmarket, in other words when the markets are doing well otherwise they can hit the floor like a ton of bricks.
Only an idiot would invest in something that they do not know what they are investing in to get penalised if they want to sell up.
If you do want to invest in something then start going around to carboot sales and picking up bits and pieces to start and selling them on Ebay or something, even if you only make a couple of quid it is an afternoon out that you are not spending in the pub.