Facebook Chief Operating Officer Sheryl Sandberg has some advice for women: Every day, write down three things you did well that day.
It's a practice Sandberg began after the death of her husband, SurveyMonkey Chief Executive Dave Goldberg, in May 2015.
"Some days it was hard — 'made tea,' " she told a packed audience at the Grace Hopper Celebration of Women in Computing in Houston in October of one entry.
"Confidence and leadership are muscles. You learn to use them or lose them."
Instead of focusing on what went wrong, Sandberg said she now ends the day by focusing on her daily successes.
In 2013 Sandberg published the best-selling book, "Lean In," which encouraged women to take a seat at the corporate table rather than shying away from fully participating.
"Confidence and leadership are muscles. You learn to use them or lose them," she told the Houston conference.
She also encouraged attendees to stay in tech, saying jobs in the industry were well paid, flexible and high impact.