Sorry this is later than I said, I just couldn't find the time!
So, when I was going on my first trip abroad, we were doing a layover to Madrid- our flight was at 9 pm, we'd get to Madrid in the morning, stay the day, and then hop on another overnight flight to Greece. Basically whatever we were wearing that first night from JFK, we would be wearing all through Madrid the next day. So, when my cousins told me just to wear sweats- I'd have to be comfortable so I could sleep all those hours on the plane- I cringed. It was my first time in a foreign country, I didn't wanna be roaming the streets of Spain in sweat pants! So I faced the dilemma of finding an outfit that would last me two nights and a day trip, that would be as comfortable as pajamas, but stylish enough to be photographed in. Here of some tips-with outfits ideas from celeb pix-and the outfit I finally settled on!
I suggest NO heels or jeans. If it is a day flight I suppose jeans are OK, since they are casual and can be styled-up, but if you're doing an overnight no matter how much you love them, they really aren't comfortable enough to sleep in. A couple of the outfits below have jeans, but they also have other style elements I like, (ex: Lauren Conrad is wearing a big comfy scarf and shades with hers). I suggest a never go wrong garment-leggings! They are great- they look chic but are just as comfortable as sweatpants- I suggest black, since they are so tight that is the most flattering color. Either with boots or flats, and a longer tee (like Katy Perry) or jersey/knit dress (like Nicole Richie). Or a new favorite idea of mine- like Kate Hudson and Jessica Alba (the first pic) a trendy trench! Always have a traveling cardigan-over sized-to keep you warm and be comfy, but it looks much better than a sweatshirt (see Eva Longoria Parker or Demi Lovato). Also bring a pair of comfy socks you can slip on for the plane, and then easily throw into your carry on. Little things that add fashion like a belt or jewelry, hat or scarf can easily be taken off for sleeping on the plane and then put back on once you land. (see Miley Cyrus and Rachael Bilson) P.S.- staples for me that are comfy and super chic are big cashmere scarves and super-sized sunglasses :)
Here are some travel fashion inspirations that were mentioned for examples: (p.s.- my favorite is the second jessica alba one!)