Our mind is the part of us that thinks. We can love God with our mind by choosing to think about Him and choosing to not think about things that God hates. It is easy to fill our minds with sinful things by reading bad books and magazines, by watching bad movies or TV shows, or by spending our time thinking about sinful things. When we put bad thoughts into our head, it is impossible for us to love God with all our mind.
In our Bible verses, Paul reminds Christians to focus on God. How can we focus on God? We can spend time reading the Bible or books that glorify God. We can watch TV shows or movies that do not include evil things or encourage sin. And we can share with others about God and His Word.
Stay away from evil things and fill your mind with God. Then it will become easier to love Him with your whole mind.