I found this in the index on my computer. I wrote it for a student a few years ago.
1) Write all pedals in simple, printed, block letters, straight up and down. Example: B#
2) Write all pedals in dark pencil.
3) Make sure that none of your markings touch any of the printing on the page. Mark pedals only where you have room to put them without touching anything else.
4) Write all pedals large enough to see easily
5) Write the pedals in where there is sufficient room to write them. They can be written between the staves or below the bass staff, as space permits.
6) Always write the right foot above the left foot. Be consistent about that.
7) Write each pedal change EXACTLY where you are going to change it. Sometimes this means writing it in the middle of a beat to avoid a pedal slide for example.
8) If one foot is going to move the same pedal again a few beats later, put a line from the first change to the second. Just write the accidental(not the letter) for the second change.
9) If one foot is going to move the same pedal again several measures later, put a short line after the first change, which will indicate that your foot can stay on that pedal, as in: B#-
Write the next pedal change of the same pedal with a short line before it, as in the example: -B#