So how long would you say it took for you to have a constant supply?

Right now I have 7 females, 3 of them that were from a litter I just had, but being that they were female I just kept them to use as breeders. I also have 2 males. I'm just starting to get into this so I didn't want to start out with 12 from the get go. What I would like to do is just get a bunch of other females(until I have about a dozen) that are ready to breed, and start following that schedule that was on the sticky. I'm not sure if I get it. I'm just trying to figure out how to get it going the best. Any advice or just a decent walkthrough would be awesooooooooooome! I'm gonna go read that sticky again and see if I could get some more out of it.