Step 0: Have Rust and cargo installed in your environment. (Instructions) Or, you can enter the cs128env docker environment where they are already installed for you.
Step 1: Enter your directory of choice (cd ...). In cs128env this would be /home/vagrant/src.
Step 2: run git clone https://github.com/kaushik327/rust-fft.git and cd rust-fft.
Step 3: Put your .wav file of choice in rust-fft/audio.
Step 4: Go back to the rust-fft folder, run cargo run, and follow the instructions given. The output .svg files will appear in rust-fft/output after the program is done running.
voilà!