What is a good process for studying and learning chess openings?

I’m an intermediate club level player, but I’ve never taken much time to learn a lot of chess openings. I know general opening principles (develop quickly, control the center, etc.), and recognize a decent number of openings during play. But I think it’s time to buckle down and start studying specific openings and their variations.
I’m wondering if anyone has suggestions for a good *process* to use for this study. Suggestions on particularly good books to work with would be welcome too, but more than that, I am trying to set up a solid program. Should I just start with one opening and memorize it? Work through variations one by one? Start with only king openings, or only queen, or…? Is it better to study on my own, or with others at buy medicine online without prescription the club? How much time should I spend?
And so forth.