Travelling light is a tricky thing to do. But it is possible!
You just need to be a bit organised and do a bit of planning and you should be able to fit everything you need quite easily into your carry-on case for a short trip.
As the recipient of very frequent flight and hotel upgrades, there's a lot to be said for looking stylish and tidy when you depart, fly and land. Airlines and hotels work on the principle on incongruity, if you look the part (stylish & tidy), you're far more likely to get the good stuff coming your way.
Here's my wonderlist of how to travel light with a week's worth of outfits in a very small case.
First of all, get yourself a good carry on.

I've had this Samsonite one for a while. Works a treat, lots of compartments and pockets and its literally been all over the world with me.

Get a good wash bag and a makeup bag. I'd recommend getting two separate ones instead of a ginormous one for both. Its easier to pack two small wash bags than one big one and its a bit easier knowing where everything is. I've got Tiger Tem versions very similar to these by Aspinal and I have a blue one and a brown one.
I always travel with a roomy handbag as well. Ideally one that I will use as my day bag at my destination.
Top Row Left - Michael Kors do some really great reasonably priced bags. I love the colour on this one and its only $138!
Top Row Right - Michael Kors Messenger, handy cross body bag in a fab colour. $198
Bottom Left - Proenza Schouler - what's not to love about this fantastic satchel?
Bottom Right - Chloe still are one of my favourite handbag brands for their laidback luxe.
Then you need one pair of fab jeans, a pair of denim shorts...(and a few tank tops and easy tshirts). Jeans are great as you can dress them down by day with a tank and flip flops, or throw on some bold jewellery, and some high heels and you've got an easy evening look sorted. Go skinny, bring back your bootlegs and a pair of tiny denim shorts will be versatile enough and hardly take up any space. A Wear also do some great priced womens jeans and denim shorts too.
A couple of cute day dresses. I love maxi dresses more than ever right now. I'd normally take a couple of day dresses so maybe one short and one long.
A couple of sexy party dresses. As you can see my colour palette is pretty much pink, purple and black. Fabulously feminine and supremely sexy! The good thing about all these dresses is they could work for anything, from a wedding, to a dinner date, to a cocktail party. Just imprint your signature style to your look with your accessories and you're good to go.
One, maybe two fabulous clutch bags are all you need. I normally take two very flat ones as they hardly take up any space and in case I'm hanging with the same people a lot, I won't look as if I'm always wearing the same thing! Look after your accessories and they'll last a lifetime. Always pack your handbags/clutches/shoes in the cloth bags they come with when you buy them.

A cardi/pashmina to keep you warm at night. I've got a few pashminas from MyPashmina, they're 100% cashmere, supersoft and come in the most fabulous colours. And as I'm a regular customer, you get to benefit too. Use the discount code YUMMY when you order to receive a 10% discount.
Some day time shoes...no matter what have to be VERY comfortable. I like to get around on foot wherever I go so i need to know my shoes won't make mincemeat of my tootsies by the end of the day.
Some night time shoes...I've got the red ones and I get ridiculous numbers of people asking about them. They are very glamorous and very showgirl-ish but I LOVE them!
And don't forget your bikini...
And there you have it. A week's worth of clothes, pretty much made up with pieces I have in my wardrobe (or very similar items) so I can guarantee it works!