When I first started... I burned my dogs out in a pen. I worked them three or four times a week. Then we'd turn some the hogs loose and have a "staged" hunt.
Now I will put a pup in the pen a few times to show what a hog is and get them baying... but that's it.
I'll start hunting them in the woods when they're a year old... once they've matured.
This is how some of theses old timers in my neck of the woods do it... seems to work out pretty good.