I have a dry erase board near my machine and I write down the size of needle and date each time I change it. I also write down any tips I need to make the quilt I'm working on or # of blockes needed, etc. For used needles that can be used again, I saved empty needle cases for each size needle I use and put the used needle in there. FOr example, I save a 90/14 needle in an empty 90/14 case. I write "used" on the package so I know it's not a sole new needle left in the case.