Fixing Shitty Image When Connecting TV To Computer

I connected my LG 43" TV to my MacBook Air, got shitty image:

How I fixed it

Here's how I fixed it:

Fixing input lag (also called display lag)
- First thing is to make sure the refresh rate setting is correct ( ≥ 60hz) in Displays >
  - If refresh rate option is 30hz max, make sure the proper resolution is selected
    - I had selected a weird resolution (2040x1080), that's why higher refresh rates were not available
  - I chooses 120Hz, it's best
  - If you can't still pick a higher refresh rate, make sure:
    - your TV actually supports 60Hz+ refresh rate and
    - you use a proper HDMI cable, at least 2.0 (1.4 and lower are locked at 30Hz on resolutions higher than 1080p)
- Set your TV to Gaming mode.
  - Specific settings for LG TV:
    - Picture mode: Game
    - Go toy All settings > Picture > Additional Settings
      - Make sure HDMI Ultra HD deep Colour is eneabled for your HDMI port
      - Make sure Instant Game REsponse is enabled for your HDMI port
Fixing cropped image
- Go toy All settings > Picture > Additional Settings
  - Go to aspect ratio -> Original
  - Just Scan -> turn it On. This fixes common problem known as Overscan. By default it's on Auto and usually this means it's off.
- This should solve the cropped image problem.
Fixing washed out colors
- Simply go to your computer settings and test different color profiles.
- For my MacBook Air, it's in Display > Color Profile.