We are aware of what contrast is. What if the contrast in the photo is not just in terms of light and colour, but rather in terms of physical objects? Then what we have done is juxtaposition. If done correctly, this is one of the best techniques to create a photo that shall speak volumes for itself.
It might feel tricky at times, the simple way is to find contrasts, in terms of physical description, age, emotion, weather….virtually anything and everything.
In terms of shooting format, RAW has advantages over JPEG as there is more data ready at your disposal if you want to tweak the photo, such as a better dynamic range, scope of sharpness, noise reductions etc. While in a JPEG photo, smaller size, faster write speeds are the positives. If you need immediate delivery of the photos, go JPEG. But, if you have time to post process and maybe change a few things around, RAW it is. JPEG is like the print photo, while RAW is still the negative. Personally, I shoot RAW.