V. … Therefore a twofold efficacy is ascribed to the sacraments according to us: the one moral and objective, by which the sacraments make present to our mind that object, to signify and seal which they are destined (by which means, faith is either excited or confirmed and, it mediating, hope and sanctification are increased); the other covenantal, by which God (sealing by the sacraments his promise or covenant) confers the very things promised upon the believing soul or even a greater sense and perception of these already conferred and produces by both greater operations. Hence the sacraments are rightly called exhibitive … a moral exhibition by which that grace is objectively exhibited to the mind and with it, at the same time, really to the believing soul. [Francis Turretin, Institutes of Elenctic Theology, 19.VIII.5; v.3:363]
In the Reformed tradition, the ministry of the pastor is called the ministry of Word and Sacrament. That is because it is not just the preaching of the Word that is important for the health of the church, but also the administration of the sacraments. Since it is faith that saves, faith in the Gospel message, the sacraments are not medicine that saves (like health packs in FPS video games). Rather, the sacraments are visible words, exhibiting the Gospel message in a different, more sensory form.
The sacraments are "visible words," which is that they are of the same type as the preaching of God's Word. Just as preaching sets forth and exhibits Christ and the Gospel, so that those who hear and believe will be saved, so likewise the sacraments exhibit Christ and the Gospel, so that those who partake and believe will be saved. Just as preaching puts forward Christ and His benefits for our instruction, discipleship and encouragement, so likewise the sacraments puts forward Christ and His benefits for our instruction, discipleship and encouragement. That is why Turretin calls it a "moral" efficacy, as it influences and moves people through means of exhibiting the message to our mind.
The correct way to partake of the sacraments of baptism and the Lord's Supper is to treat them as visible words. Partake in faith, and meditate upon the biblical truths these signs convey as you partake of them. Then, and only then, will you benefit from the sacraments for your encouragement and strength. As you are baptized, or every time you witness a baptism, remind yourself once again of what Christ has done for you on the Cross to save you, and how He has forgiven your sins and united you to Him in faith, so that you are now saved from your sin and given new life in Him. As you partake of the Lord's Supper, remember the atoning death of Christ on your behalf as you partake of the bread, and in the wine thank God you are now under the New Covenant and not under the Old Covenant of Law and Works, so that you are now under grace not works. In such manner, you will derive great benefit for your souls through the sacraments, as God has intended for you to do so.