Memoirists in particular must let readers see and experience what they see and experience.
Here is one example.
The original scene, in Russia just after World War II:
We were walking down the street one day when a mad woman began swinging a big piece of wood with nails in it and screaming that she had lost her family during the war and did not know what to do anymore. “My dear husband, my Anatoly, is not here anymore. He’s dead! I can’t live without him,” she cried out loudly.
We were scared. She swung her two by four wildly and struck a man who was walking by and some others. The police arrived and took her to the mental institution, and the ambulance picked the man up and took them to the hospital.
One possible rewrite:
Marina and I took our usual route to school that morning. As we passed the bakery, a woman came charging at us, swinging a two by four with nails in it. Her eyes were wide and glassy. “Anatoly is gone—killed!” she screamed. “I can’t live without him!”
We froze, and she turned to a man who had just come around the corner. She hit his shoulder from behind and he fell. She swung at others, hitting some and missing some. Two policeman came and grabbed her arms. She quit screaming and started sobbing as they carried her away. A few minutes later, an ambulance came.
They have the same number of words, but the rewrite has more information to help the reader experience this event.
Notice how just a few key details let the reader see the bigger picture.
We don’t need to know what the woman was wearing or what she looked like. Her “wide and glassy” eyes show us enough.
We don’t need to hear her say that Anatoly is her husband. The context of war and loss means we can assume he is her husband or son, and their exact relationship is not important. (It’s also a bit unlikely that she would announce this to everyone in this situation, which might throw some readers out of the action.)
By adding a few, specific details, writers can make scenes vivid and realistic for the reader and entice them to turn the page.