Short guide to using LiquidCTL.
First of all you need to install Homebrew via your terminal. It is a very simple operation. Find several videos on Youtube that explain how to do it. Just be aware that you will have to disable the SIP (System Integrity Protector).
Once Homebrew is installed, search for LiquidCTL via Homebrew on your terminal.
Just enter in the command line:
brew search liquictl
and install it with the command:
brew install liquictl
Once liquidCTL is installed, you should look for the program manual on GitHub where it shows you, as well as the supported hardware, the way to change the color of the motherboard LEDs.
Personally I keep the LEDs of the fans white and the LED on the left of the processor green. This is the command to set it:
liquidctl --pick 1 initialize
liquidctl --pick 1 set sync color fixed ffffff
liquidctl --pick 1 set led1 color fixed 008000
The first command line initializes all the LEDs on the motherboard, as suggested by the manual;
The second line sets ALL LEDs to white;
The third line sets led1 (the one to the right of the CPU) to green.
To choose the color set the RGB code of the color you are interested in, "ffffff" is white "008000" is green.
Finally, to launch liquidctl at login, use Automator and, through the "Run shell script" section in "Workflow".
In the dropdown set bin / bash and enter the commands you want. Launch the Automator file at login.
#!/bin/bash
/usr/local/bin/liquidctl --pick 1 initialize
/usr/local/bin/liquidctl --pick 1 set sync color fixed ffffff
/usr/local/bin/liquidctl --pick 1 set led1 color fixed 008000