Sally,
I tend to go for the more relaxed look of slippers and pipe for the flight, lol.
In another note for those interested I flew back from Madrid yesterday and don't know if it was just my flights but they were having a big crackdown on size of hand luggage.
Was checking size of everyone and putting a good few into the hold (a few people not happy but to be honest no sympathy from me, rules are rules and just because you get away with it on one flight isn't an excuse).
So be careful with dimensions of hand luggage.
That was with BA.
Mick