The first thing you want to do is make sure the words related to the photograph are recorded. Don't use fountain pen, use a pencil, but make sure those words are recorded somewhere. Once the words are no longer connected to a picture, you lose the relationship between the people and events in that photo. That is so important. The next thing I'd say is to take care of your pictures.
Cases are ideal.
Some protection from the elements, sharp changes in humidity. Take care of them so they can last to the next generation. The other thing is to collect the stories of the people that make the picture important. All that makes the picture come alive. One of the best things to do if you have a whole box of old photos is to sort them by generations.