That's a great question, and something that frustrates a lot of us in apartments or using public bins! When a bag slips down, it makes a mess and is just a hassle. Based on my own trial and error, here’s what really works.
First, the golden rule is dry bin, sticky bag. Make sure the inside of the bin is completely dry and free of old debris. A damp or greasy surface is a slip-and-slide waiting to happen. Give it a quick wipe if needed.
For a more secure hold, use bag liners or caddies. These are rigid plastic frames that sit inside your bin. You clip your bag onto them, and they prevent the entire bag from being pulled down when you take it out. They're a game-changer for large bins.
If you don't have a liner, create anchor points. Before putting the bag in, tie a loose knot in each corner of the bag's top. These knots can catch on the bin's rim or handles, acting as little hooks. You can also use binder clips or specialized bin hangers from a hardware store to clip the bag's edge firmly to the rim.
Distribute weight evenly. Don't throw all your heavy waste to one side. An off-balance bag is more likely to tip and slip. Put heavier items at the bottom in the center.
Finally, don't overfill. When a bag is stuffed beyond the bin's rim, the outer surface presses against the bin wall, creating friction that holds it up. An under-filled bag has no such pressure and will collapse. Fill it to just above the rim before tying it off.
A little prep goes a long way. Using these tricks will save you from messy clean-ups and make taking out the trash much less of a chore. Happy (and secure) disposing