How do I use the color accent mainly the color swap.
Next to the hot shoe is the mode dial, you can see the Full manual (M) mode, plus an ample supply of scene modes (Presets). There you can see the color accent and color swap features. Color swap does just as it sounds like: you swap one color for another.
Go to the camera's Function Menu and press My Colors. If you get more trouble, you can check the camera manual.