In the title you said first time BP owner, so I am curious as to what other snakes have you kept and for how long did you keep them?

+1 on the accurite or any other good digital temp/hygro.

Make sure to place the sensing devices close to the substrate, where the snake will spend most (if not all) of his/her time to get the most accurate readings.

Oh yeah, what kind of BP is he/she anyways?

Cardboard can be use to help control humidity, just make sure the air does not become stagnant, this will facilitate the growth of mold and parasites

Two heating pads with temperature controls could get pricey best to be creative with what you can afford, its more fun