Picture Style
If your camera has picture style option; explore its Monochrome (for B & W) and Portraits style. These style usually adjust Sharpness and Contrast etc. If you want bright colors; boost Saturation. For soft skin looks for women, children and pets; increase Sharpness. To get the better range of tone; decrease Contrast a bit. If you have the option to apply filters to control lightening and darkness of skin tones; use Red or Yellow filter to lighten the skin. Green will darken the skin.
Grid OverlaysEnable the grid overlays; if its 3x3 grid; keep the subject on any of the two lines. The corners of middle rectangle is considered golden points.
FlashYou can use the built in flash as fill flash if subject is in shade and background is strongly lit; sunny days. The built in flash can also be used for catchlight (the sparkle in the eyes). Dont use its full power; use the Flash Compensation to control it.
Action PortraitsKids playing etc; use Shutter Priority mode. To freeze the action use 1/2500 shutter speed. For focusing use Al Servo. Use Continous drive mode; chances will increase that you will get a nice action shot!
Post ProcessingTake many pictures; then select the best picture and if required do post processing. Shoot RAW as DrShaggy has suggested; doing so; you dont have to select Picture Style and apply filters; you can do that in post processing easily. When cropping; never crop at joints (knees etc) Increase color temperature to give your subject a healthy look. Keep the background clutter free. Use the brushes to blurr unwanted things out.