Portrait photography, like any photography, is an art.  There are several factors that go into getting a great portrait.  As a beginner, you need to experiment with different aspects of portrait photography before you know what works best in which setting.  Here are some tips and tricks that could help you as you begin your journey as a portrait photographer:

Light

For portraits, good lighting can make the difference between an average portrait and a great one.  The trick is ensuring even lighting on your subject.  Excessive light (like bright sunlight) can create harsh portraits while insufficient light will give you dimly lit grainy portraits or shadows over parts of your subject’s face.  Depending on outdoor or indoor shoot, try to get a good balance of light that will give you clear portraits.  Experiment with a flash, reflectors, a thin curtain, natural shade, different angles of light, etc. to get the optimal lighting.
 

Aperture

The aperture of your camera lens will decide the depth of field for your portrait photograph.  A wider aperture will give you a shallow depth of field, which means that the focus will be on your subject and the background will blur out.  In contrast, a smaller aperture will make the entire scene to come into focus.  For portraits, a wide aperture (f/5.0 or less) is always better so that the camera focuses sharply on your subject instead of the backdrop.
    

Shutter speed  

The shutter speed would determine the time of exposure.  The general thumb rule is that the brighter the light, the less the time of exposure required, while dim light would require longer exposure.  In natural outdoor light a shutter speed of 1/100 or 1/200 (or even less if the light is very bright) would work fine.  If you are shooting indoor or at night, you would require a shutter speed of 1/50 or more.  Again, experiment with shutter speeds to see what works best for your setup.
    

Zoom  

Use of zoom depends on distance of your subject from the camera and the kind of portrait photograph you want.  If you are shooting from a distance, you would definitely need to use zoom in to get a clear shot.  Also, if you are going for close-up portraits, zoom is essential.  However, the extent of zoom can be tricky but is crucial to the clarity of your photograph.  Not enough zoom and you would end up with distant portraits, too much zoom and you may end up focusing on unflattering aspects of your subject’s face.  Play around with the zoom a little bit before you go for the shoot so that you have a feel of what would be the ideal zoom.
    

High-speed camera  

You need a high-speed camera when shooting action portraits.  There are a range of high-speed cameras in the market today and using one would go a long way in helping you get stunning action portraits.