Hard to say. It depends on how quick you learn, how much of a perfectionist you are, the complexity of what you're trying to print, how much reading you've done prior, and what help you have access to.
If you take a weekend printing course, you could be comfortable by the end of the weekend. Or it could take substantially longer (months of solitary toil and yet still something doesn't quite click).
There really are too many variables to say. But if you're still uncomfortable and struggling in a month's time, I'd recommend finding a short course (even if you have to travel).