Decreasing double crochet is a technique used in crochet to reduce the number of stitches in a row. It is commonly used to shape garments or create decorative effects. To decrease double crochet, insert the hook into the next stitch, yarn over, and draw up a loop. Then, insert the hook into the next stitch, yarn over, and draw up a loop. Yarn over again and draw through all three loops on the hook.
Decreasing double crochet can be used to create a variety of shapes and effects. For example, it can be used to create a fitted waist in a garment or to create a decorative border. It is an essential technique for any crocheter who wants to create garments or other items with complex shapes.