This afternoon, we packed our suitcases for our trip to Madrid, Spain. Mind you, we don't pack big suitcases. We always take care we just have hand luggage because you pay a lot less for your airfare.
It takes about 5 minutes to pack such a small suitcase. The trick is to pack only what you really need! Like underwear for the days you're away, pajama's, some basic wear like T-shirts or tops, 2-3 pair of good quality linen trousers (can crease as much as they like) if you like wearing trousers or the same amount of cotton or linen skirts. Two pair of sandals and one pair of shoes in which you can walk kilometers. The rest goes into your handbag: your smartphone, sunglasses, those products which you have to show at the check-in (like cremes, deodorant, perfume - mind, don't take too much), an e-reader, a sunhat (we have cotton ones, which we bought years ago in Vancouver, Canada - they easily stow away in a leftover spot), your identity card or passport, credit cards or money (best is not to take overmuch), a comb, ...
Even if you travel for a longer duration, we don't pack big suitcases. My granddad always used to say: don't pack a suitcase you can't lift. We have never had to pay for overweight and still have more than enough to wear. It's best to work with basic garnments, like skirts or trousers of a very good quality which can be worn everywhere.
Needless to say we're really looking forward to this trip. At last warm sunshine (we haven't got this in the course of July and what's passed of August), outdoor dining, ... Will be great and very relaxing.