It isn't always possible to fix a zip, you may need to take it to your local seamstress to replace the zip entirely. Here are some fixes for the most common repairs, courtesy of the Sunday Times.

1. Often zips get stuck. Once you have cleared any fabric from its path (do this carefully to avoid making a hole), take a graphite pencil and rub the tip along the zip’s teeth that are closest to the zip puller — this should do the trick to help the zip slide past. If it isn’t closing properly when being zipped up, the pencil trick should work too.

2. *Warning* Invisible zips are the most difficult to fix, but these step-by-step instructions should help. If you succeed in doing this, you should have no problems with visible zips. Are you up for the challenge?

a) When one side of the zip has popped off and out of the slider, the best place to start is the bottom.You will need to access it, so you may need to unpick the seam on your dress/skirt etc a bit. Don’t worry, you can fix that later. The bottom of the zip is often left exposed, so you shouldn’t have to unpick too much.
b) If there is a bottom stop, you must snip it off (carefully please!), as we need both sides of the zip separated. Pull apart to separate.
c) Remove the slider from the side it is still attached to via the bottom of the zip.
d) Feed the slider back on to the zip by pushing the zip tape down and wiggling through the top of the head. Stop the slider when it gets to the teeth. Do the same with the other side of tape, ensuring they are both the right way round and are even. NB: wiggle carefully, as the teeth are very sensitive and if one of them is slightly bent the wrong way, you will need to snip it off to make it smooth.
e) This is where it gets tricky. You want to slide the slider up at the same time as pulling apart the zip tape below the slider, so it forces the slider back on to the teeth and the teeth to lock into place. Use your thumb and forefinger to hold the end of zip tape in place and pull the slider up with your other hand. This can take a few goes; just don’t force it with too much pressure.
f) Once the slider is back on, you want to check it is working from top to bottom.
g) Because we removed the bottom stop, we now need to put something in its place to ensure the slider doesn’t come off the end. If you don’t have a soldering iron at home (odd!), then take a needle and thread and stitch across from one side of the tape to the other. Finally, carefully sew up any bits of seam you had to unpick to remove the slider.