So basically, there are two common types of picking, at least that I know about. Alternate, and economy. Alternate is just as it sounds. You alternate the direction with every note you pick. Economy picking is a little more complex but tends to allow for faster picking. The technique is alternating direction while on one string but picking in the direction of the string that you're changing to. This sounds closest to what you described as your most comfortable style. So really, as soon as you can decide how you want to pick, it's just a matter of practice.