The number one problem people seem to run into when trying to pack, for short or long-term travel, is shoes.
And rightfully so.. there is no "one shoe" for every occasion, and it's extremely frustrating trying to match shoes with outfits, comfort with style, functionality with taste, etc.
The absolute best and only advice I can give you is.. quite simply, a reminder that no one cares what you're wearing when you travel. I go into this concept extensively in No One Cares, Except Maybe You.. but in short, at least in terms of style.. you don't need to worry about your shoes; if you stick to simple, neutral colors and don't get too fancy with your outfits, you can wear the same pair every day.
This is where having just 2-3 outfits will actually simplify your shoe selection; just pick a style, for example.. "stylish hiker," and go with it, every day.
Remember, when you're in a different country, whether it's by the clothes on your back, your hair color, your skin tone, or the constant look of confusion on your face... you already stand out... so stop worrying about having the right outfit for every occasion, and that will free you up to pack just one or maybe two pairs of shoes.
Now in terms of functionality, that's a different story; at the very least, you'll likely want sandals for the beach, comfortable walking shoes for daily use and shoes or boots for hiking.. Personally, since I pack the absolute minimum, I pack just one pair of black trail-running shoes, which work fine for trails, long walks, working out and general, daily use. Yes, they look horrible with pants, but I have to remind myself that I'm literally the only person who notices or cares; and if you're really doing travel right, you shouldn't be wearing pants at all.
Now I realize it can't or won't be that simple for everyone.. so this is where you may want to get a little creative; for example.. if you're a serious hiker and like to have ankle support, consider packing ankle braces instead of a full pair of hiking boots, you get the same support just in less space; or if you see yourself doing a lot of boating or water sports, consider water shoes, and then leave the sandals at home, remember, you can always buy a super cheap pair of sandals wherever you are, and tie them to your bag or leave them behind if you're heading to cooler climates.
I also highly recommend shoe inserts that can be replaced as you wear through them - these can be found literally anywhere in the world and they give your shoes a bit more life.
I do pack and recommend a pair of barefoot sandals for beach days and hostel hangs, they take up almost zero space and can be attached to the outside of your bag when traveling (or inside, whatever works). I have a pair of Xero sandals that I've been using for years, they are extremely thin (by design) and very durable; although you could argue not the most comfortable until you get used to them.
Lastly, I highly recommend not skimping on this one aspect of your attire, they're low-risk in terms of losing them, and the right (or wrong) shoes can make or break your trip; your best bet is to find the most comfortable, neutral looking, multi-functional shoes available; because you'll be wearing them all day, every day, and for every occasion; remember, comfort is king, and style is just a dirty, forgotten step-child.
Last lastly... for those of you who get the reference in the title of this post, I love you. :)