Remembering is vital for Torah and a tonic for everything. Man’s whole duty is to remember that he is a Jew; that he is duty-bound to be vigilant and guard himself from any sin; and that he must keep all the commandments of Hashem — whether Scriptural or Rabbinical — in all their most minute details with all his heart, soul and being.
Remember to always fulfill the verse, I have set Hashem before me always (Tehillim 16:8); to be aroused to fear and love the great and awesome Hashem; and to cling to Him at all times and every moment. If possible, from time to time one should recite arousing verses such as, I have set Hashem before me always and “Fortunate is the man who does not forget You” (Siddur, Mussaf of Rosh Hashanah), and other similar verses.
Remember all the sins that people regularly transgress without a thought, such as the bad traits of haughtiness, anger, jealousy, vengefulness and impatience; or excessive eating, idle chatter and slander; reciting prayers and blessings quickly and without intent; stealing and deceit; and in general violating various commandments, with bittul Torah (not studying Torah) being the most severe.
Above all, remember the punishment that is due for evil traits and for committing sins; how serious they are; how and what one can do protect himself from them; and how to wage war with cunning against the Yetzer Ha-ra.
It is also necessary to remember all of one’s sins. This helps the person in several ways: It prevents him from becoming arrogant; and he will try to correct his misdeeds and to fulfill the requirements of repentance. For he will believe that all the sins he ever committed are all laid out before God — not one of them is missing, since there is no forgetfulness before Him — and therefore if he does not correct them he will one day be judged for every one of them.
One must also remember all of the kindness that Hashem ever did for him, from the day he was born, and thank Him to the best of one’s abilities. How good and proper it is to choose some item as a reminder of Hashem’s wonders and humbly say, “I am unworthy of all the kindess!”
It is also proper to always remember the exaltedness of God and His individual Providence.