Focus only on the present day and hour.

Rabbi Tarfon said: "The day is short, the work is great, the workers are lazy, the wages are high, and the Master is insistent."pirke avot chapter 2 mishna 15

Rabbi Nachman says: How can we meet the heavy quota of the work is great each and every day? The answer is to focus only on today, as the Book of Psalms advises: "Today! If you heed His voice!" (95:7) This is a fundamental rule in the service of Hashem:Focus only on the present day and hour.

from the Breslov Pirke Avot page 104

It is nice to know that our Rabbis have been telling us to take it one day at a time for a very long time. It didn't originate with AA.