The easiest option is simply remove your lens (and switch your camera if DSLR to sensor cleaning mode to raise the mirror and open the shutter) to expose the sensor and use a rocket blower to blow air onto the sensor, hopefully knocking off some of the dust particles. This is not the most effective option but it is doable by anyone.
The second option requires you to use a sensor swab to wipe your sensor. Not all users are comfortable doing this by themselves. In that case, just send your camera to your trusted camera store or service centre and have the technicians there do it for you. Previously I sent in my Sony NEX-6 to the Sony Service Centre for sensor cleaning. The turnaround time was around a week but it was free of charge as my camera was under warranty then. It's a pity that Nikon does not offer free sensor cleaning for its camera under warranty. So I try to take advantage of free sensor cleaning opportunities during Nikon events. For example, I recently attended a Nikon event and you can see the pictures below showing my Nikon D610 sensor before and after cleaning:
|Before sensor cleaning: there were many dust particles, particularly along the left edge.|
|After sensor cleaning: only 1 or 2 dust particles left.|