Those three numbers are fine and good but we want to see what they mean in 3D space, right? Traditionally, a Processing sketch would be used to read the serial data and convert it to a 3D rotation - but thanks to Web Serial API we can use any Chrome browser - a lot easier than installing Processing!
At the time of this tutorial, you'll need to enable the Serial API, which is really easy.
Visit chrome://flags from within Chrome. Find and enable the experimental web platform features
In Chrome, visit https://adafruit.github.io/Adafruit_WebSerial_3DModelViewer/
Verify you have 115200 Baud selected (it only really matters for non-native-serial devices but might as well make sure its right)
When the security window pops up, pick the matching Serial/COM port for your board running the AHRS sketches. Make sure the serial port isn't open in Arduino or something
You'll see the serial port monitor on the bottom and a 3D bunny on the top. Try rotating and twisting the sensor to see it move!