Link to LDS.ORG: https://www.lds.org/youth/learn/yw/ordinances-covenants/essential?lang=eng
We make covenants when we receive ordinances such as baptism, ordination to the priesthood, and temple ordinances. A covenant is a sacred agreement between God and His children. God sets specific conditions, and He promises to bless us as we obey these conditions. Making and keeping covenants qualifies us to receive the blessings God has promised. When we choose not to keep covenants, we cannot receive the blessings. Our covenants guide the choices we make and help us resist temptation.