I generally use 10 pt. font. Sometimes when the information just doesn’t quite fit onto one sheet, I will decrease the font size to 8 pt. or 9 pt. Even the smaller sizes are easy to read.
If the entry is too large to fit onto one page, I add the word “Continued” to the bottom of the first page and to the top of the second page.
If the entry contains a list of items installed or a list of repairs done, I will often place a bullet symbol at the beginning of each item. This makes the entry easier to read rather than a bunch of items listed continuously within a paragraph.