Lynzi - go to walmart.. They have thermometer / hygrometers. The brand is accurite, they're digital. It's about 2" x 3" fits in my brinsea, laying on its side. You might get different temp readings between the brinsea thermometer & the accurite one. I go by the brinsea thermometer.
As far as water. I bought a mixed bag of thin, thin sponges, but they were the size of a sheet of paper. I cut them in strips about 1.5" - 2" wide and long enough so that they curl into the bottom of the water well and comeback up to lay on the floor of the bator under the hatching tray. You have to play around with the amount of water in the well with the sponge and how many sponges you need to maintain the humidity you want. Then I take a piece of aquarium airline, cut one end at an angle and slide it thru the air vent on top down thru a hole in the egg tray right into the water channel. When the humidity gets low I use a needless syringe to injet water down the line into the channel. Add small amounts at a time and wait about a half hour to recheck humidity, before adding more water.
Don't give up................. it takes practice and patience to figure out how to get the best hatch rate from our bators. I've had some awesome hatches and some really crappy ones, It will come.