Building a CanSat

I am part of the AIAA SPARC rocketry challenge where I have to build and launch a CanSat by the 10th of October. This is going to be both a challenging and exciting challenge. The primary mission that I have to accomplish is to build a CanSat that can record the following: Air temperature and Air pressure. The secondary mission involves developing a GPS system in order to track the satellite upon deploying. I have the proposal approved and now the next step is to build the CanSat.