The Psalms are a collection of prayers in the Old Testament, found in the middle part of the Bible. We read a psalm out loud as a prayer. The psalm for the day is found by determining the day of the year. There are only 150 psalms, so when you get to day 151, start over with Psalm 1. We also start over when we get to day 301.
You can determine the day of the year here: www.epochconverter.com/daynumbers