Ashly,
I have never written a book on howling. The most important thing is to have a good idea where the coyotes will be when you begin your stand. Coyotes here in my area are out in the open fields at night, where they hunt for mice and such. Not long after daybreak, they head back to the thick stuff. Most of my calling is done from a ridge top, and I hunt during the day. Early morning is best, with the last hour before dark being a close second. I read posts where guys are howling way too much. Coyotes do not often howl in that fashion. I howl once, twice, maybe three times and then go silent for several minutes.
I have almost zero experience in calling at night. Night time calling works very well if it is legal to use a light while calling in your state.