The Rebbe was asked about a problem someone was having. The response was that the individual had not memorized the beginning of chapter 41 in Tanya and had not internalized it in his heart. That section in Tanya is tells us that Hashem stands over a person and sees everything he is doing, speaking, and thinking.
This section of Tanya should also be written on paper and be in one's pocket at all times. Additionally, it should written in your heart and be with you wherever and whenever.