Packing for a week or more for a vacation in Europe using only a carry-on can be done!
|This will go into my carry-on, electronics will go into black bag, and I will be wearing the flights clothing.|
We will be flying Ryanair once we get to Spain and they have very strict (and small) luggage requirements. You can have one free carry-on that is no larger than 21.6 x 15.74 x 7.87 inches including wheels and handles so think child size suitcase.
So even though you want to look good, you also have to be practical. Stick with pieces that mix and match. My daughter and I spent 16 days in Europe with no luggage since they lost it on the trip over. You CAN get by with only one pair of jeans by washing them every night when you take a shower. Same with you undergarments and other clothing. It's also a good excuse to go shopping.
Hope this helps you with packing your small carry one.