Since we make the Sign of the Cross before and after our prayers, many don't realize that the Sign of the Cross is a prayer itself. It should be said with reverence; we shouldn't rush through it on the way to the next prayer.
Using your right hand, you should touch your forehead at the mention of the Father; the lower middle of your chest at the mention of the Son; and the left shoulder on the word "Holy" and the right shoulder on the word "Spirit."