I looooove travel hacks!
I always overpack but lately I got to enjoy the freedom of just travelling with a backpack or carry on. My best packing hack is putting everything inside your shoes: underwear, socks, belts, anything that fits! I promise it saves sooo much space it was a life changer for me!
What is yours?
Agree about the shoes! Use every inch of space you have.
I have a fold away puffer coat that has a huge inside pocket (that it folds into), so I put anything that won’t fit in my bag in this massive pocket 
I’m also a bit obsessed with travel accessories and have a travel size everything, mini brush, toiletries, towel - even a travel yoga mat!
If you roll everything up and then use a compression band to squeeze it together, you can fit A LOT on some of these ‘underseat bags’ - but have to watch the weight depending on the airline!
Packing cubes! not sure if it’s a hack but you can definitely fit more in there. Also if you’ve done too much shopping and ran out of space, you can get a” travel pillow” fill it with clothes and boom a secret carry on item!
Stuff your travel pillow - genius, I;ve never thought of that!
Travel towel all the way! Sometimes places you stay, the towels are a bit dingy. A travel towel is thin, light, easy to dry, easy to pack, and I used it for so many things other than drying my hair! It can be a scarf, a shawl when visiting special sites, a yoga mat, a temporary wall or cover of your bed. The Hitchhiker’s Guide to the Galaxy said it best: never leave home without your towel!
Mine is probably less exciting, but it’s genuinely saved me so much stress 
I make a packing list in my Notes app and never delete it. After every trip, I go back and tweak it based on what I actually used. If I never touched an item? It comes off the list. If I found myself wishing I’d packed something? It gets added.
Now I have different versions like “weekend trip,” “beach,” “cold weather,” and “carry-on only,” so I’m basically packing from a checklist that’s already been tested instead of starting from scratch every time. I’m definitely stealing the shoe trick though—I always feel like I’m wasting that space!
Take half the clothes and twice the money.
For me it’s packing clothes in ziplock bags! You don’t realize how much space you can save until you try it. Just pop your clothes in, squeeze out the air, and you’ve suddenly got so much more room in your backpack. You can buy special vacuum bags for even better results, but an ordinary ziplock and a bit of effort does the trick just fine!
Does carrying more in air-tight conditions make the backpack any lighter?
Not at all, but it does wonders for space and organization! Everything becomes so compact. Instead of juggling 10 loose items, you just pull out one neat bundle. The only thing to watch out for is wrinkles. Anything delicate will probably need a quick iron when you arrive.
I love vacuum bags! I always use them nowadays, especially in colder months when you have thick or padded clothing.
I also try and think what I actually need to take, and what I can buy on arrival (I’m really guilty of overpacking suncream and toiletries!)
I also am terrible for buying so much food and souvenirs in location, and end up with more luggage to take home than I originally came with, so I always try and under-pack on the way out, or take clothes that I’m considering donating, and leave them behind so I can pack the case.