Try adding metal o-rings down the sides of your pant legs! You can use silver or gold, depending on your preference.
This upcycle is super easy because the metal o-rings from your local craft store will come in a kit with an application tool. All you need to do is mark where you want each ring with a sharpie and hammer in the rings with the tool provided.
It's an affordable trick as well because you most likely already have a hammer lying around. All you need is the o-ring kit.