We've all had to deal with a loose or popped button. Twist ties make a good quick fix.
Photo by Tasha
If the twist tie can fit in the button holes, there's no shame in using it if you don't have any string around. Note that this trick is safest with jumpers, since they have a relatively wide weave. With other fabrics, you may run the risk of making bigger holes, so use with caution.
There are a lot of other quick tricks for fashion emergencies in Mashable's article below, so hit the link below to check them out.