Well, there are two parts to that question: 1. measuring and 2. interpretation of the measurements.
Measuring is really not very hard. It only takes about 45 minutes to an hour to map out the response at your main listening position. Use the test tones that you can find at the RealTraps website to map out your room between 10 Hz and 300 Hz. For each frequency, record the SPL (C weighting, slow) using your sound meter. Then transfer the readings into Excel.
Interpretation of the measurements is another matter entirely. I am still learning about this.
