Loose photos or on your phone ? Either way you can separate by subject matter...like family , holidays , nature , food, sights ...Or by year...
Shirley: Here are a variety of ways to organize!
I put my pictures in a shoe box and made dividers. I have the year on the divider and separate the photos by year. When anyone is looking for a photo they know approximately where they can find them. Everything after 2005 or so is on a CD drive in an album labeled by year.
You could get photo albums for different years/events/people.