In 2015 Dave Thomas, whose name is on the Agile Manifesto, gave a talk named “Agile is dead - long live agile”, addressing the intent behind the manifesto and the Agile Industrial Complex / cult-like movements which spawned from that.
I've watched this video a few times, and I recommend the part at 25:43 which describes agility. To repeat it here:
1) Find out where you are
2) Take a small step toward you goal
3) Adjust your understanding based on what you've learned
4) Repeat
I think this is useful as a high-level guide, and it's both easily memorizable and generally memorable. I use a silly mnemonic "FI-TA-AD-RE", and I come back to it whenever I'm working and get to a point where I have to ask myself "What the hell am I doing?"
https://youtu.be/vqz8ND-N1hc