Filling in a self-appraisal of your job performance before your annual or semiannual review has become the norm in most businesses. And in most cases the self-appraisal form is standard, with several categories relating to specific aspects of your job description, each with a numerical ranking and an area for further explanation. The form usually has a final section for ranking your overall performance and areas that need improvement. In most cases, both the employee and the manager conducting the review fill out the same form and exchange them before the review.
Balance your self-appraisal. While keeping a positive tone is important, do not exaggerate your strengths and by the same token do not dwell on or magnify your shortcomings. An overly positive or overly negative self-appraisal gets the whole review off on the wrong foot and puts the manager in an awkward position.
Emphasise your contributions to the business throughout the form. Use specific examples of the contributions you made and the benefit to the company both in the more descriptive sections and in the various job responsibility categories.
List your personal accomplishments over the year. Include phrases such as "learnt a new programming language," "attended two training seminars" and "earned a new professional certification."
Admit to some areas that need improvement. Nobody is perfect, and even an excellent employee will have some weaknesses he needs to work on. If you have a problem area in your job, offer a specific performance metric that you will improve by a certain amount by the next review.
Be thorough and thoughtful in filling in the self-appraisal. Rushing through it and just filling it in with short answers reflects poorly on your attitude about the job.