When recording someone, or yourself, there are a few tips that will make your experience go that much smoother.
Renting. Now of days, you can record on your phone, but if you want to have a slightly higher quality recording, many people opt to use an actual audio recorder. You can often rent audio equipment at your local library, at your school, or through community programs.
Questions. There are a few questions you should find the answers to before committing to a recording device. How much many minutes does your device record? Do you need to charge it? How do you get your files off the machine, and in what format are they? When was it lasted tested for functionality? Is it compatible with x device? Etc.