I never seem to learn my lesson - I am referring to using life lines when knitting. I will not detail how to put in a life line, because I never use one. There are articles a plenty on the net, including this one from Knitting Daily. A life line is kind of like a book mark, and can save you time and grief should you make a mistake. Just insert a life line to hold the place of the last row you know doesn't have a mistake, maybe every 5-10 rows or so, or whatever you feel comfortable with. And should you make a mistake beyond that life line, all you have to do is rip back to that point.
Myself, I usually just work backwards until I reach my mistake; this is handy if the mistake is caught in the same row it is made, or just one or two rows back. Many more than that, and if it won't cause a major change in the flow of the fabric, I tend to just let it go and deem it "character". If I am not far along in the project, I just frog completely and start over from the beginning. Or, set the project aside for so long I forget where I was in the pattern; in these cases, I just shrug and frog and put the yarn back into my stash bag.
You may know I have been working on a very big cabled afghan - if I calculated correctly this puppy will be 6 feet by 6 feet. This is by far the largest project I have ever worked on. I can't for the life of me figure out why I wanted to do this. I've flubbed a few times, and this afternoon did it again. So, deciding to make lemonade from my lemon, I decided to share with you how I work backwards to fix my mistakes.