One thing to know about mistakes in knitting is that we all make them. Fortunately, knitting is easily corrected, and you'll learn from any missteps. Once you learn to correct them, you'll be happily on your way again.
Count your stitches often as you work, especially after casting on and after making increases or decreases. This habit will help you catch many mistakes. If your stitch count is less than it should be, it may be because a stitch has dropped from your needle.
Use a crochet hook to correct a dropped stitch, whether it has dropped one row or several rows (a running stitch).
Step 1: Hold the knit side of the work toward you. Count the horizontal strands between the two needles to determine how many rows the stitch has slipped. It's important to begin with the very first strand closest to the dropped stitch. With the loose horizontal strands behind the loop of the dropped stitch, insert a crochet hook into the loop from front to back. Catch the first horizontal strand and pull it through the stitch (fig. 20a). Repeat the step with each horizontal strand until the dropped stitch is back at the current row.
Step 2: Place the stitch on the left needle untwisted, with the right loop of the stitch in front of the needle (fig. 20b).
Continue in pattern.
Learn basic crochet stitches on the next page to add decorative edges and more to your knitting.