indeed, he who watches over Israel will neither slumber nor sleep.
Slumber can mean the appearance of sleep, or inactivity. Not only will God not sleep, He won`t even ever have the appearance of sleep or inactivity. He is sovereign and He is watching over you, no matter what time of day, or what type of circumstances you are in. God is also concerned about the group (Israel, the church) and the individual - you!
Begin by reviewing the first 3 verses. Then work on just today`s verse. Then all 4 of them together.
Start first thing when you wake up - whenever you have your first idle thought time - whether that`s lying in bed for a few minutes before you get up, showering, fixing breakfast.
Continue to review throughout the day, whenever you have a minute to spare. You can get a lot of reviewing done in just a minute or too!
Developing the habit of memorizing and meditating on scripture takes commitment, but it so worth it.
LeRoy Eims on the importance of Scripture memory: "I think two of the master strokes of the devil have been to convince people he doesn't exist, and that Scripture memory is only for children. He remembers the humility of defeat when Jesus Christ, who was tempted in all points like as we are, met him with the Word of God." (What Every Christian Should Know About Growing; p. 26-27)