Packing cubes is a great space-saving strategy for travel! I started using them a few years ago and they make such a difference in keeping things organized in your luggage.
There are different-sized cubes you can get on Amazon or at stores like The Container Store. I usually do one for shirts, one for pants/shorts, one for socks/underwear, etc. It cuts down on digging around in your bag since you can just pull out the whole cube.
Some other tips - roll your clothes instead of folding them to save space. Compression packing bags are handy too. And don't overpack - focus on mix-and-match pieces that can be worn together in multiple outfits.