Last week we saw how observing our mind can help us to develop sincerity. One of the best ways to embed that into our lives is to start a journal. You could try journaling daily for a month.
In your journal reflect on any inner justifications you made to yourself that day. Maybe you played an event over in your mind, exploring it from different angles until you felt good about what you did or said? Or maybe it was something smaller. You could have made an excuse to yourself to skip meditation practice or to miss a deadline for work.
Be curious and honest about how you justified these things to yourself. Have sharp eyes and a warm heart.
At the end of the month review the entries to see if there are any patterns emerging. In this way the journal becomes a mirror to help see your insincerities.
Here is a 15 min podcast made by a group of students who took up "Sincerity" as a focus theme of study for 40 days.