When you commit

It pays to take some time before you commit to review your changes and create an appropriate log message. You are publishing the newly changed project anew every time you commit. This is true in two senses:

If you later don't like your log message, it is possible to change it. The svnadmin setlog command will do this locally. You can set up the script http://svn.collab.net/repos/svn/trunk/tools/cgi/tweak-log.cgi,tweak-log.cgi to allow the same thing remotely. All the same, creating a good log message beforehand helps clarify your thoughts and avoid committing a mistake.

You should run a svn diff before each commit and ask yourself:

Defining a log entry policy is also helpful --- the Subversion hacking.html document http://svn.collab.net/repos/svn/trunk/www/hacking.html is a good model. If you always embed filenames, function names, etc. then you can easily search through the logs with search-svnlog.pl http://svn.collab.net/repos/svn/trunk/tools/client-side/search-svnlog.pl.

You may want to write the log entry as you go. It's common to create a file changes with your log entry in progress. When you commit, use svn ci -F changes.

If you do not write log entries as you go, you can generate an initial log entry file using the output of svn status which contains a list of all modified files and directories and write a comment for each one.