1. Pick A Strong Subject
As silhouettes don't have any detail and are, essentially, just an outline, picking a subject that has a recognisable shape and strong detail around the edge will produce shots that are more interesting. Possible subject choices include:
Big wheels at fairgrounds or those found in cities.
Statues, which can be found in most parks and gardens.
Trees, particularly on misty mornings.
Tunnels or bridges make great frames for subjects when silhouetted.
People but remember that shooting them side on will show more shape when still.
People in action - if they're jumping or forming an interesting frame with their legs and arms, shooting straight on can work well.
2. Choose A Light Source
Any subject that is surrounded by bright tones can easily appear as a silhouette. The most obvious light source to use is the sun as you can use it at the beach, in town, in your garden or even inside as long as you're working near a large window or close to a set of patio doors. But really you can use any light source, you just need to make sure it sits behind your subject.
3. Switch The Flash Off
When you take your camera out of its bag
and use auto mode to take a shot of your subject sat against a bright background, generally the flash will fire to lighten the foreground and even out the exposure. This is usually fine but as we want to deliberately underexpose our subject, you need to make sure the flash is turned off.
4. Underexpose Your Shot
When working in auto mode, most point and shoot cameras will work out the exposure and where it needs to focus when you press the shutter button half way. So to trick it into creating a silhouette, simply point the camera at the brightest part of the scene you're photographing, press the shutter half way down and don't let go of it. Re-frame the shot then press the shutter button the rest of the way to take your shot. This should fool the camera into giving you the exposure you want but you may have to try exposing from different parts of the image to create the silhouette you're looking for. Try using the Sunset Mode too to further enhance the silhouette you're trying to create.
5. Check The Shot's Focus
The problem with half pressing the shutter button to get the exposure you need is that the camera will also focus on that spot too which can mean your silhouette can lack crispness. If this happens and you can adjust the focus manually, pre-focus before you take your meter reading. You could try using Landscape mode as this will let the camera know you want to use a small aperture so your shot has front to back sharpness. If your camera features exposure compensation you'll be able to select -1 or -2 to deliberately underexpose your shot. This means you shouldn't have any problems with focusing either as you won't have to move the camera.