Hi Susan,
This requires a little bit of music braille knowledge, but is easy once you get it. If you get a hold of the Music Braille Code PDF, on page 2 you'll find some helpful symbols.
Dots 6, 3 is the opening music code indicator
Dots 56, 23 is the music code terminator.
A time signature is given with the upper number in the upper portion of the cell followed by the lower number in the lower portion of the cell. Only the initial numeric indicator is needed.
So, when you come across a time signature in a literary passage, use the opening music code indicator, then the numeric indicator followed by upper cell 4 and then lower cell 4 (or 6 and 8 or whatever the time signature is), and then put the music code terminator before the next literary word.
If the time signature is followed by punctuation, it gets a little more involved, so write back if that is the case!
Patrick