Rock the Right Material
Do not wear a Spongebob backpack at 20-something years old. Look for backpacks with leather, canvas, and lightweight nylon material for a more formal vibe. Other details to try: studs, stripes, florals, tribal prints, and symbolic motifs. You want your backpack to look high fashion not inappropriate.
The utilitarian backpack in its modern, zippered glory dates back to the 1900s. Therefore, the backpack will always be in style or needed in some kind of way.
Will you be getting your “backpacking” on?