According to the standard way of Defect profile document format:
Title should be short, precise and point the issue correctly.
Though the title reflects the issue in short, define the bug in few lines which gives brief description
Steps to reproduce:
Here clearly mention the steps where you face the error and what are the steps to be reproduced for it.
Mention the steps right from invoking a browser , entering application url to the place where issue arised.
Screen shots play an important role for effective bug report.Try to attach the screen shots
which make others to understand easily on looking it.
Sometime the issue may be over looked while reproducing, hence attach the screen shots for necessary bugs.
Make an habit of it.
Some data like environmental details may also help developers to understand what exactly is the cause by knowing the environment.
Environment details such as Operating System, Browser and its version etc..
Some browsers may not support some features and some issues may also does not occur in some browsers.
Hence this information helps developers to resolve issue sooner.
Never report against any single person directly as XXX person developed this .
Severity /Priority :
Mention the severity level and priority level, as hat going to tell the sequence of bugs to be concentrated first
Simple Language :
Use simple language while explaining about any issue which is understood by anyone