Making a photographic silhouette is very easy and fun to do.
The conditions required for this type of shot are back-lighting and a subject on the horizon line. For example, in my photo here, the bull elk is right on the horizon line where there is nothing but sky behind him. This component of a silhouette shot is what makes the subject really stand out.
The procedure to get a shot like this could not be easier. I just shoot my camera in the direction of the brightest part of the sky and take my meter reading from that location. Then I recompose the shot to include the subject right where I want it to be in my viewfinder. On this photo I paid attention to the rule of thirds and kept the subject in the lower-right third of the image.
Give it a try. Making a silhouette is fun and easy. And the results can be stunning!