How to shoot OCF (Off Camera Flash)

I strongly recommend you study the LR screenshot in the comments. Routinely, the sun in this part of the world is F12-14 in the late afternoon because of clear air. At high noon, the sun is usually f18. Yep, more than f16. We have very clean air around here. Today, I would guess it was F12. Because light behaves as a physical object when it comes to bounce or skimming, the highlights of the model are quite bright. At the same time, the shadows of the hill behind her are quite dark. This creates a problem. Even though I can light the model with my strobe to equate to the sun, I would cast the background into darkness were I to do so. Why? Because I have to adjust my camera to the highlights by reducing the ambient light that is coming in. Note the shutter speed is 800th of a sec. I could go much faster. The result, as mentioned, would knock the shadows into darkness. So what is the lesson here? OCF is an amazing tool to let you control the light. But you still have to take the ambient light of the world around you into consideration. What I do to make it fast and easy, is expose for the background situation. Once I have a background that I like, I bring in my strobe and adjust it on my model or subject. It's a two step process. 1. Background. 2. Subject. 

I bring in one strobe at a time, adjust, then coach the model into best position and shoot away. After about 5 minutes or less in late afternoon the lighting of ambient will have changed and it's time for more adjustments. 

Using only one strobe with a smaller modifier allows for dramatic shadows. Note the angle of the model allows for light to skim across her belly. The strobe is 180 degrees of the sun, creating the same shadow effect on the opposite side from the sun.