Learning to use a modern DSLR camera in fully manual mode. I now intuitively understand the relationship between the control inputs of shutter speed, aperture and ISO and the outputs of image brightness and depth of field (I still mostly use auto-focus). I have sufficient muscle memory for the controls that my big complex camera is truly a point and shoot device and I can have a few pictures in the can while the crowds with their mobile cameras are still waiting for the things to focus. Don’t get me wrong, I use my iPhone camera all the time, but if I want to get pictures that are different from most other peoples, I can.
I’ve also learned to take a portfolio perspective to photography (building sets of pictures that tell a story) rather than instantly uploading everything in a competitive search for ‘faves’. I’ve rediscovered younger me’s joy in photography, whilst posting less than I have for years.