For the past few months, I have been knitting a poncho that has three different kinds of simple cables in the design with the pattern repeats being 8 rows long. A few weeks ago, I noticed that there was a mistake on one of the largest cables about 3 or 4 repeats back. At one point, I decided to just leave the mistake alone and continue on. I think I knitted about 5 rows and then let it be for a few weeks. I could not leave that mistake in the work because I knew it was there and it was noticeable.
Sunday night, I took the circular needle out of the project and pulled the yarn back to a few rows previous to where the mistake was. I then carefully placed the needle back through the stitches and started knitting on it again. After I knitted a few rows, I noticed another mistake and had to back up about a row and a half. Now, each time I finish cable stitches, I double check them so that I won't have to back up the work again.
I should probably use a "lifeline" and thread a thin yarn through the stitches at the beginning of a pattern repeat. That way,if there is any mistake in the pattern repeat, I can pull the yarn back to the lifeline and start from there again. Also, there is less chance of dropping stitches when pulling the yarn and/or placing the needle into the stitch.