Terri Spath's funds kept client money safe during the coronavirus rout, financial crisis, and tech bubble. Here's how she's done it, and how she's already prepared to make a killing in the aftermath.

· Terri Spath is the CIO and a fund manager for Sierra Mutual, which can boast strong results during the last three major market meltdowns because of its emphasis on avoiding losses. 
· A critical part of their approach is tracking 30-day moving averages for all their investments on a daily basis and never hesitating to sell,...