Comments
Express yourself in code, not in comments
Comments are no excuse for bad names
Use methods instead of comments to segment your code
Write comments to explain the why, not the what
Design goes into the design documents, not the code
Comment with ", not with *
Put comments before the statement they relate to
Delete code instead of commenting it
Don't do manual versioning
Use FIXME, TODO, and XXX and add your ID
Don't add method signature and end-of comments
Don't duplicate message texts as comments
ABAP Doc only for public APIs
Prefer pragmas to pseudo-comments