What I do, and I'm pretty sure you'll hear is the best advice is a protein shake (in particular whey protein) within 20 mins of working out. I see you're in the UK - at the moment Holland and Barrett have got their whey down to £10.66 a drum (908g/2lb) which is less than half price. It's approx 18g of protein per serving for between approx 1.5g - 2.5g of carbs depending on what flavour you get (IIRC banana is the lowest)

I normally have a double scoop after a workout - I take it in a zip lock bag, put water in my shaker, add it then shake. If you get a proper protein shaker (I've seen them in H&B a couple of times as well as gym suppliers) it will have a mesh thing inside which helps with mixing so you don't get lumps