Darning is an old technique that is most often used to fix and reinforce holes in socks. With darning, you are actually weaving the yarn over the hole, creating a new patch that replaces the missing knit fabric.
Use this basic darning tutorial, How to Darn a Sock to learn how to darn. To apply this to a sweater, use a small embroidery hoop to assist you in darning instead of the wooden egg used with sock darning.
To darn a sweater, you will want to select a yarn that matches the sweater to better hide your handiwork. On the other hand, you could pick a contrasting color of yarn and go for a funky look.
You will need a darning needle for this project. This is simple an oversized needle with an eye large enough to fit yarn into.
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