It’s a fact of life that if you knit, you’re eventually going to make a mistake. The trick is knowing how to fix it, because all mistakes can be fixed.
The first thing to know about is how to unknit. Say you've knitted a few stitches and realized you're off the pattern. You knitted where you should have purled. To go back a few stitches, the best thing to do is work backward. Look at your right hand needle and notice the most recent stitch. You can see the loop around the base of that stitch. That is what you want to pick up, putting it back on the left hand needle. Then you can let the new stitch slip off the right hand needle. Repeat this process until you get back to where you went astray.
If your mistake goes back to a previous row, you may want to take the more drastic-sounding step of removing your project from the needles. I know, I know. We live in fear of dropping stitches off our needles. But you can do it in a careful, controlled way. Once off the needles, you can actually unravel the project one stitch at a time, so you can control how far back you rip out your work. Once you've ripped out the mistake, you slip your needle back through what will be an identifiable row of stitches. Count to be sure you've got the right number of stitches. And always be careful.
Both ripping out and unknitting can get tricky if your work includes increases, decreases, or yarn overs, but it can be done. You can even unknit a bind off if necessary, though it requires patience and thought.
Then there is the dreaded dropped stitch. The first step with a dropped stitch is to pick it up on something, a spare needle, stitch holder, something so it doesn't unravel further. Now that the stitch is secure, slip it onto your right hand needle. Then find the horizontal bar behind the stitch. That's what your stitch should have been twisted around. Slip that bar onto your right needle, as well. You should slip both yarn loops onto the needle entering from front to back. Then use the left needle to slip the dropped stitch over the bar, just as for a pass slipped stitch over or bind off. If the stitch dropped down more than one row, just repeat this process for each row. Once you’ve picked up your dropped stitch, slip it back onto the left needle and continue with your project.
The best advice I can give if you have a tricky mistake to fix is to put it aside until you are calmer. Do not try to fix a big mistake in the throes of panic as you can easily make the situation worse. The time I royally messed up the complicated blanket I had worked so hard on and immediately tried to correct the problem without thinking, I got so upset, desperate to fix it, I wound up with nothing but an unraveled mass of yarn in my lap. (It all worked out in the end, though, as I restarted the blanket the next day and it came out much better on the second effort.)
As a final thought, you have another option when you make a mistake in your knitting: embrace it. You are making a handmade item. Perfection isn’t the goal. Be willing to let a small mistake be like the lumps in homemade mashed potatoes: proof that it’s not from a box (store).
What’s the biggest knitting mistake you’ve ever made?