Assalaamu alaikum Sara,
Umm… whereabouts are you coming from? I suspect you'll find a lot more headscarves in the UK than you might think (UK members correct me if I'm mistaken…). I know in Canada, several people have told me they see more women with headscarves here than in their native lands in the Middle East.
There are different styles of headscarf, so you can tailor your look a bit. Personally, I prefer a two piece cotton knit blend. It is stretchy, but breathes fairly well, and there are no pins or falling ends of cloth to bother with. You can sleep in it, if necessary, it's that comfortable. But quite a few young women like the diversity of colours and styles they can put together when wrapping and pinning their scarves with less stretchy cloth. These are very attractive, but you need to know how to do it, and there are pins to contend with. It also gives some women a headache (because of tightness).
(smile) Then there are the dupatta-like variations (from Pakistan), the headwrap style you see coming out of some African countries, the peaked cap Turkish styles, the East European kerchief styles… (smile) Muslim ladies like their fashions, too. And if you are in an urban center in countries where there are a diversity of immigrants… chances are, you'll find a style that speaks to you, and that is not as weird as you may think it would be.
As for what else you can wear… well, abayas are very comfortable and appropriate in hot, dry climates (like Saudi Arabia)… but in a rather damp and cool climate… I'd suggest investigating what the local people wear, and adapting it for the level of modesty you are aiming for. This is also cheaper. (smile) It's rather fun , you know, to go to second hand shops and look for clothes that you can mix and layer. (smile) You can create an inexpensive, modest and beautiful look all of your own!
(smile) I hope you enjoy your stay in the UK.
May Allah, the Strong, Protect you.