Tears and holes in vinyl upholstery are an eyesore - and, if left unrepaired, they tend to get bigger and uglier. Having a pro repair one can be expensive, but you can do it yourself with liquid vinyl. It's inexpensive, and you can do a surprisingly professional-looking job.
Basically, you rub the sticky liquid vinyl into the hole or tear with a spatula. Then you put a piece of "graining paper" over it and slide an iron over the paper for up to 60 seconds, to cure the vinyl. When you remove the iron and paper, presro! - you've patched the hole.
Liquid vinyl, available in many auto-parts stores and some hardware stores, come in various colors. If you can't match your upholstery, a vinyl repair kit ($7.99 in my area) is available that includes five bottles of liquid vinyl: yellow, red, blue, black and white. By mixing these together, you should - in theory, anyway - be able to come very close to a match.
To make the repair as professional as possible, read the directions thoroughly and then make a few practice repairs, making holes and cuts in the graining paper and patching them. This will take only a few minutes, and it'll give you a feel for the material.
Wipe the spatula clean from time to time. to keep its surface smooth, and be sure the surface you're working on is clean. If not, wash it with detergent, rinse and let it dry completely.
If the none of the various graining papers that come with the kitis a perfect match, pick the closest one - if you've come close enough on the color, the slight difference in grain won't be very noticeable.