How do I make Objectivism my Modus Operandi?

Short answer: All you have to do is think!

Long answer: it you're relatively new to Objectivism, a good place to start is learning about the Objectivist virtues (rationality--the "master" virtue--plus independence, productiveness, pride, integrity, honesty, and justice). For a more full understanding of these, and in order to answer other questions that are bound to come up in your life, you will eventually want to delve deeper into ethics, epistemology, and metaphysics. And you'll also want to gain more clarity over the political and cultural landscape--but how it is, and how it should be.

There are numerous Objectivist works of nonfiction addressing all these issues (though I'd recommend not getting too deep into these until you've read at least Atlas Shrugged, The Fountainhead, and Anthem). Here is a good reference:

http://www.aynrand.org/site/PageServer?pagename=objectivism_sugread

Finally, you'll probably find Leonard Peikoff's "OPAR" book to be supremely useful.

By the way, let me caution you very strongly not to treat Objectivism as a set of rules to live by, as a dogma, etc. It's very easy to fall into that trap, especially for people coming from a religious background (which was my background). The reason I mention this is because Objectivism isn't a "modus operandi" (it's a philosophy).

When you can afford it, I would also recommend two lecture series by Dr Peikoff, "Understanding Objectivism" and "Objectivism Through Induction," both available at the Ayn Rand Bookstore.

JJM