The best advice is hidden in one of the links in the article: Always include some sort of session identifier, as to identify all the log messages that belongs to a session or transaction.

The articles speaks briefly on log severity levels, which is key to manageable logs. Make sure to specify what levels the application uses, preferably in some design document if one is being used.

For example, high severity error messages, should be only situations that should not normally occur or problems internal to the organization. For example, end user invalid credentials is not a high severity error, but invalid credentials towards the backing data store is.

Personally I tend to keep log severity thresholds local to the session, because that's the kind of filters I normally want to write.