Most DIY storage organizers on TikTok feature square wire nets joined with wire net connectors or zip ties, but you can also use wire trays or metal cooking racks.
TikToker @madeby_miko connects wire nets to form the bottom, back, and side structures, creating a hollow cube. Add as many shelves as you like, and place plastic trays on them.
You can also use wire trays, like TikToker DIYer @dana_burke. Position one tray vertically, then place the other two at each end to form the top and bottom sections.