Inform your manager first through a brief and professional letter stating that you are leaving to pursue other interests or opportunities.
Don’t wait until the last minute to advise your organization, Make sure you don’t speak negatively of the company, your manager, or peers during this transition time.
Complete your projects and finish your job. If possible don’t leave anything undone. Clean up your work area and arrange material for your replacement. Remember to leave the company assets behind. Unless you brought something from home or paid for that item with your own money, it should stay on the desk.
The exit interview is not your chance to be boastful about your future or irate about your past. Don’t gloat that you are moving on to bigger and better things. Also, don’t take this time to berate your boss or reveal things about your co-workers that you never voiced concerns about before.
Leaving with class and grace will never come back to haunt you, but burning bridges may certainly come back on you, due to the fluidity of today’s job market. You never know when paths will cross again.