Everything that each user has already said on here is fantastically accurate, especially eilidhkegg's responses! T last year was my first festival and I was 18; it was without a doubt the best weekend of my life. So much so that I'm going again this year, despite driving to Scotland from Coventry - a vast 10+ hour drive. It's 100% worth it though, not just for the music but the AMAZING atmosphere. The Scottish people that I encountered were so wonderful and welcoming and honestly, no one cares that you haven't showered for days because we're all in the same boat. Personally I feel that the Refresh wristbands are a waste of time and money, because you'll spend ages queuing just to end up dirty again shortly.
I was going to answer your questions, but the aforementioned users seem to have got that covered. What I will say though, is you're not allowed to take your own alcohol into the events area (where the music is) and your bags WILL be searched on entrance, so try to get as drunk as you can before you enter (ha!) You'll definitely be ID'd at the bars, but T do this great thing where you buy drink tokens separately to avoid everyone counting their pennies and holding queues up. If I remember rightly, I took £200 spending money and actually returned with £20, so I'm either just really good at budgeting money or it's a good value festival!
I was pretty lucky last year as we just happened to camp somewhere that was near toilets (but not too near - gross), food stalls, water tap and the actual events area. Choose wisely! The walk from the car park to where you get your wristbands is absolutely soul-destroying, especially in extreme heat like last year, and I'm afraid it only gets worse when you have to walk miles to the camping areas. Don't let this put you off though, because I remember shouting all the expletives I could think of and exclaiming "**** off am I coming to a festival again, I'm going home" often. However, once you're enjoying a nice cold beer with your mates with your tents all set up, you'll be laughing!
I spent the weekend eating burgers and food like that mostly, but I stumbled across this amazing little section called Healthy T in which obviously... healthy food is served. It's refreshing to see such a fantastic range of peculiar food, because at one point I was feeling so malnourished and dehydrated that a bowl of pasta was honestly a godsend, hahaha. A strange selection of meat such as ostrich and kangaroo is also served in burgers, which I unfortunately didn't try last year, but that's something I'll do this year. Although it's something most festival-goers don't take notice of, T organisers really stress the importance of not getting too wrapped up in the moment and forgetting to eat - I hate to sound like a worrying mother but my brother got ill last year because he kept drinking and blanked food.
LECTURE OVER. Haha. Basically, T in the Park is my favourite festival because of the amazing lineup, welcoming atmosphere and the fact that absolutely no one judges your dirty, unwashed self... everyone embraces it. If I haven't bored you to tears, feel free to pm me, I love talking about T as I'm sure you've noticed! Maybe see you this year too x