Oh, lining those tall, narrow kitchen bins can be so frustrating, right? The standard bags are always too short and slip right down. After much trial and error, I've found the absolute easiest method.
Here's the simple hack: Use a larger size trash bag than you think you need. For example, if your can is roughly 10-12 gallons, try a 13-gallon kitchen bag. Don't pull it all the way up immediately. First, drop the bag in and let the excess material bunch at the bottom. Then, pull the bag's top rim over the edge of your can and *fold the excess overhang to the outside*, creating a sort of cuff. This extra material at the bottom fills the space, and the outside cuff secures it firmly. No more slipping!
A couple of pro tips: Make sure the can is completely dry inside before you start. If the bag is still slippery, a tiny piece of double-sided tape on the outside of the can's rim works wonders. For a super sleek look, you can also use two smaller bags, one lining the bottom half and the other the top, overlapping them.
It's a simple switch that makes weekly trash duty so much smoother. Hope this helps you as much as it helped me