When first converting to Catholicism, I felt a bit uncomfortable with the extra "formality" of prayer… seemed like a big change from the more natural-seeming conversation I was used to. What I realized is that stuff like the Sign of the Cross isn't some obligation you have to do before and after, or else God won't hear your prayer. It's a way to sanctify the prayer itself, inviting God's grace to make us more fully present to Him, and Him to us. In fact, it's a great thing to hold loving, easy conversation with God throughout the day, and you don't need to be following a ritual every time you do it. At the same time, these rituals are valuable for us, and they've been passed down to us for a reason. Do you have to make the Sign of the Cross before everything you do? No. Would doing so be spiritually profitable? Of course.
The same kinda thing goes for the finer theological points of prayer. I think the common explanation is something like: "We pray to the Father, through the Son, by means of the Holy Spirit." Does this mean you can only address God the Father? Not at all, considering how many traditional prayers address Christ and the Holy Spirit directly. The nature of the Blessed Trinity means we can never fully grasp the complex dynamics of this sort of thing. But this should not become a stumbling block in our prayer – God does not expect us to understand Him by reason. We have only to love, and He will enlighten our understanding by Faith. Not that study is bad, of course, but be patient with the intellectual aspect of things. Most important is what the heart does.