Hope the following helps...
1) Silhouette shots
Meter the background, take note of the reading (shutter speed, aperature). Dial to manual mode, focus and shoot the subject without the use of flash.
2) Get the subject well exposed as well as the background
Same as above, but use flash. You can attempt to you reflector. Btw, easier said than to be done.
3) Get the subject well exposed but background totally blown out
Take metering and focus on the subject and just shoot. Flash/reflector can still be used.