Deuteronomy 5:32 Ye shall observe to do therefore as the Lord your God hath commanded you: ye shall not turn aside to the right hand or to the left.
Observe means be careful, listen faithfully, pay thoughtful attention to, the Commandments that the Lord has given you so that you may do them. Read, mark, learn, and inwardly digest the Word of God. Memorize, think about, and meditate on the Commandments and their meanings, implications, and applications to your life. Let them sink into your brain and your heart until they become a part of you and your lifestyle.
We consciously make a decision to obey the commands of God when faced with a choice; but even more, we unconsciously, naturally, almost automatically, obey and do the right things as a general rule after our soul has been trained in the Way. This is the normal response of the believer who spends time alone in private with God and His Word, and spends time with fellow believers in public worship and hearing the preaching and teaching of the Gospel. We speak and act out of who we are inside after we have been changed. Inward change comes as a work of God on the heart, not by selfish works of the flesh to try to do better. Inward change comes from the response of observing the Word.
The outcome is a more upright life that stays on the blessed narrow path (Jesus is the Way). It turns neither right nor left by rationalizing actions, excusing behavior, or justifying the self. We abide in the vine.