Gleaned from Linux Server Hacks

• Create an RCS directory
• Execute a ci -i filename
• Execute a co -l filename and edit as you wish.
• Execute a ci -u filename to check in changes.

The initial time you checkout the copy, it will be locked, and this can cause problems if someone else wishes to edit it; you should probably edit it once and put in the version placeholder in comments somewhere at the top or bottom:

$VERSION$

and then check it back in with the -u flag to unlock it.