Mine are all digitally and done by date.
I name the main folder the year of the months:
2009
And then inside them I list the months Jan-Dec
Inside each month, I list the day and a little note of what it was:
April 26 Baleigh's Birthday Presents
April 26 Chuck E Cheese
So when I go back to look for something I know what day it happened and what was in each folder.
Im sure you were asking about people who print photos. We are military so we are always on the move so all my photos have to remain digitally and then displayed on my Digital Photo Frame and swapped out in my picture frames
Good luck with your search to find the best way to sort those photos!