To generate common-use phrases and sentences, use it as a substitute for "up to now" or "up to then." Some examples for you:

"The new law establishes a cutoff for activities that hitherto have been overlooked."

"We exchanged casual glances, she and I, which hitherto had been meaningless."

There is also the less common usage that means "to this place," as in this example:

"You, the one in the red shirt, come hitherto this instant!"