Reply: Pros hold a shotgun mic overhead just out of the camera view, aiming at the actor. AKG makes good ones. A long shotgun mic works better than a short shotgun mic. Here is a link:
AKG shotgun mics
If you are on a budget, you could gaffer-tape a regular cardioid (or ideally, hypercardioid) microphone to the end of a wooden dowel or bamboo pole. That mic will pick up a little more background noise and room acoustics than a shotgun mic will, but it might sound good enough for what you are doing.
Another possibility is to use a lavalier (clip-on) mic like the newscasters wear. Have the actor wear a thin shirt, and tape the mic under the shirt about 8 inches below the chin. If you can equalize the mic signal, boost the highs around 10 kHz a few dB to compensate for the muffling effect of the shirt. Tape the cable in place so that the mic does not rub against the shirt and make noise. Band-aids work well. Be careful not to cover the grille of the mic with tape or Band-aid.
Here are some links to lavalier mics:
AKG lavalier mics
Crown GLM-100 lavalier mic