Hiya,
First i would check out what the temps will be like in your destination, its a great help knowing before hand, although you obviously can not guarantee the weather.
For travelling i wear loose clothing, something you will be comfy in
eg, 3/4 trousers, t shirt and a thin jacket/cardigan

For night times i take skirts,dresses, trousers (thin jeans or 3/4) vests, thin t, shirts( say i have 4 things for the bottom half i will take 7 tops so that i can mix and match outfits, saves space in your luggage) a few pairs of sandals that i can wear with every outfit, this is where the thin jacket comes in handy again, you can stick it on at night if it gets a bit chilly.

For during the day i take a 3 or 4 pairs of shorts, same for bikinis (i also mix and match these) 3 or 4 vest tops, 2 sarongs and some comfy flip flops.

Dont forget your suncream, also take some washing line and a few pegs with you to tie up on your balcony or in your bathroom for when you rinse your clothes/swimwear, you can get washing detergent in a small tube to take away with you.

For your nights in london, i would wear what i would usually.

I have wrote this as if you are a woman, sorry if you are not

Loulou

I take roughly the same as Lou Lou. However I also take a hat and sunglasses. If you plan on doing a lot of walking maybe a comfy pair of trainers would be handy .You should be able to get around a 10 day forecast on the internet, so you can plan accordingly.

Girls do you not take any underwear
Sue

Shock ! Horror ! I shall have to amend my list.

Pete and sue

Girls do you not take any underwear

Yes and no bras of course, knickers for under dresses/skirts commando everything else

Loulou