I am writing a conga part in LilyPond. I saw on LilyPond's documentation how to write conga notes:
http://www.lilypond.org/doc/v2.16/Documentation/notation/common-notation-for-percussion#percussion-staves (under the congas-style section)
It mentioned "cgh", "cgho", "cghm", "ssh", etc. for the notation, and it showed an image of those notes. I figured out that "h" is for the high part (top line), and "l" is for the low part (bottom line), but I do not know what the notes mean (for example, what does the plus sign mean?).
You will understand everything after viewing the link provided above.