Trusting oneself

I'm in the middle of planning my classes, and I'm struck by how much this process depends on my trusting my future self to figure things out. Particularly for this "bridge" class I'm teaching, where I'm teaching calculus-based physics to students who have had algebra-based physics before-- it's a new course for me, not particularly well-defined (there's no textbook, for instance) and I'm adding topics to the outline that I haven't taught before, that I'm not sure I could teach well right this minute, counting on my ability to figure it out at the appropriate time.

This is hard for me. In my quest for a more structured work environment, I think it would be a good practice to separate planning from execution, to have some periods devoted strictly to planning, and other moments devoted to carrying those plans out, and thus separating the anxiety over what I should do from the anxiety over how I should do it: the theory being that the individual anxieties are easier to handle on their own. But doing so requires me to trust my ability to carry out the plans I make beforehand.