Vacuum storage bags are essentially large plastic bags you can put clothes ... Instead, after putting your clothes inside, ...

Here's the efficient, economical way to do it: Spacesaver Premium Vacuum Storage Bags ... A small bag will fit six to eight sweaters; a medium bag, eight to 10; a large bag, 10 to 12.

But after fitting the contents of two duffels, two backpacking packs, and two large suitcases into five vacuum-storage bags that take up 1/10th of the space under my bed, I am a complete convert.