Some notes on the bottom shows things but here are some explanations.
2 horizontal lines indicate the end of one dictation set (such as a letter or notes) and the newer set.
A line down the left side (see the bottom right hand side) means rush or immediate
Circled letters or numbers, indicate that there is an addition somewhere. Sometimes people forget something and then remember they need something added. Or when you read it back to them they will remember to add something. Or you will read your notes back and want something added in the transcription. Since you can't just place a cursor somewhere and insert type, you have to write it elsewhere in the steno book.
Notice the first column, 5th line of shorthand, at the end has a letter A circled. Notice below that dictation that there is another A circled. This second A information will be inserted in that part when transcribed.
There might even be some notes in red. Sometimes insertion marks are in red or even other important factors.
I took this picture from my Greegg Simplified, Speed Buiding for Colleges, Copywright 1958
Sometimes I would do similar things. I would write the shorthand, use two dash marks for dividing up dictation letters. Then if I listed again to make sure I got everything, use the letters to reference corrections or inserts (those are the circle letters).
"Gregg Shorthand had achieved the most extraordinary success ever attained by any system in the history of shorthand." John Robert Gregg, 1922