Customizing Your Mac with System Preferences

Click the Apple menu and choose "System Preferences…"

Click the "Desktop & Screen Saver" icon.

Choose and image that you like. Dynamic Desktops will change automatically based on the time of day.

Click "Download"

Click "Dark (Still)" Click "Dynamic"

Click the Show All button

Click "General"

Click "Light"

Click a color you like.

Click the Show All button

Click "Dock & Menu Bar"

Choose the side of the display on which you'd like the dock to appear.

Choose whether you want to automatically hide and show the dock.

You can even automatically hide the menu bar for a very clean look. Just toggle "Automatically hide and show the menu bar on desktop"