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The closer the softbox is to the subject, the softer the light will be. Depends on what look you're going for. Want punchy? Pull back the light and/or pull back the front diffuser on the Apollo. Pull back the reflector a bit. Want soft? Move everything in as close as possible. Start with 45 degrees up and 45 degrees to the side, angled down toward the face. It also depends on the facial angle you're looking for. Straight on? 2/3 view? Either way, start from 45 degrees up and over, from the reference point of the facial angle. Or, you can simply go with a butterfly approach and put the light straight over the camera position, again approximately 45 degrees up, and the reflector underneath the subject's face (e.g. have the subject hold it underneath, just out of the frame.
As a starting point, you might want to check out www.strobist.com and watch Lighting 101.