Always check in very gently and briefly, turning your attention inward to evaluate how much scattering was just occurring. Is gross distraction present? If so, you know you were about to forget the breath. When you recognize a gross distraction before it completely captures your attention, return your attention to the breath and sharpen up your focus. That will keep you from forgetting. Sometimes, just identifying a gross distraction as a gross distraction is enough to make it dissipate.
I'm very sorry, please forgive me. I have crippling ADHD, particularly for college transcripts. I love ordering them so much that I forgot I was in the middle of the modding process and spent about 100 minutes doing so before resuming.