Molar heat of vaporization of water lab?

I have a lab where I have to find the molar heat of vap. of water and I have no idea how to do caculate this molar heat of vap. I need to figure out a way before I do this in-cl lab. I need to figure how to measure the temperature change when... water is steam? I'm allowed to use the following: hotplate, blance, water, styrofaom cup calorimeter, hot mitts, erlenmeyer flask, thermomter, graduated cylinder, stopper and tubing embly. I think I use the tubing embly to aim the steam into the calorimeter and make water and measure the temp of the water. I know I have to get two temperatures, m of the water, and specfic heat capicaty of the water... right? Okie, with that... how do I caculate the molar heat of vap of water?