I get frequent requests for tips and settings I use on my camera. Well here is what I do for 99% of my work. Your mileage will vary.
I never use the built in scene modes or the green auto mode. Wish they weren't even there. The modes I use are P,S,A, and M (Nikon) for different reasons which I'll try to explain.
P, or Program Auto mode. I use this all the time. It is similar to full auto but allows me to change settings in camera to meet my needs. Look, the camera is smart, sometimes smarter than me. In the heat of action, I may not be fast enough to keep up with changes but the camera on P mode can do it for me. Along with P mode, I constantly am adjusting the bias, (rear dial) and exposure compensation for the ever changing environment. I mostly use this for Action, Portraits, Landscapes, and general "Snapshots".
S mode or shutter priority. Probably 90% of my action shots are done with this. I pick a shutter speed and the camera does the rest and figures out an aperture setting for me. I still use the exposure compensation heavily. I pretty much only use this for action shots. Occasionally for Portraits.
A or Aperture priority. I set this when I'm concerned about a depth of focus. Blurred background or sharper background. The camera figures out the best shutter speed for me. I still use the exposure compensation button heavily on this. A mode is great for HDR or any photos I plan on stitching together. That way they are all in the same focus plane. Also great for portraits and Landscapes.
M mode or Manual. This one scares folks but it shouldn't. I use this exclusively for my night work or for situations when one of the other modes just won't do what I want. I have full control and must select all the settings. Really though, only purists do everything in Manual. Any of the other modes can accomplish 97% of what can be done in manual. Like I said, modern cameras are very smart. However, my night work must be done in manual. The camera can't read my mind and know how long of an exposure I'll need or what aperture will work for the effect I'm looking for.
Of course there is more detail to what I do but these are the basics. I never use auto ISO. I like to set the ISO for what I'm doing. I try to use the lowest that gives me what I want. Higher ISO equals more digital noise to deal with.
In the most controversial area, Raw or Jpg, I use Jpg for action and most everything else. Raw for night work and some portraits. My goal is to get the shot right the first time and not have to fix it later. Yes there is more flexibility post editing but not so much as to tell a huge difference unless the original shot really sucked out of camera and you are going to save the shot no matter what. Here is the rub though, after all the work in Raw editing, the final shot gets uploaded in,,, drum roll please,,,, JPG. Case closed. Please, no hate mail on Raw vrs JPG, use what you want. I make money with JPG's, not much argument.