Do not start writing the resume until you have any idea about the employer. Also, you should remember this important point: you need to show the employers what you can benefit them but not what you may benefit from them. The perfect resume must focus on the strength in necessary experience and skills that the employer may require from you. You will score more point with your knowledge about the employers and understanding of what they expect from you.
Check spelling and grammatical errors: Even the smallest spelling or grammatical error may become the reason that eliminates your name out of the list of potential candidates. So, do not forget to check carefully for any error before clicking the send button, or bringing the resume across a long way to the employer.