One of the most simple knitting tools is also the best. Stitch Markers. I just started this tank sweater Sirin, by Melisa Goodale. It is very lacy and requires some concentration. The pattern only calls for two stitch markers, which would be adequate. But I have ripped out so many lace garments from missing one yarn over (three rows down) that I finally got smart. I place a stitch marker for every repeat, and it has saved me a lot of aggravation and ripping out! It is such a simple and easy fix for stress free knitting.