If you know how to simplify it, feel free to do so!
Linux version
Firstly, open the script by executing "./linux_xmriginst",
If you already have XMRig installed in "~/xmrig/build", you can change the config by choosing the second variant.
If you want to install XMRig, choose the first variant,
Find your Distro.
Then, it's installing depencies, also updating databases.
Enter your Monero Wallet address.
Choose your pool.
It's compiling XMRig, and here you go!
After everything is set up, execute 'cd ~/xmrig/build' and then either './xmrig' or 'sudo ./xmrig' for better performance!.
Windows version
Open the script by double clicking on "windows_xmriginst.exe",
If you already have XMRig installed in "YourUsername/xmrig/", you can change the config by choosing the second variant.
If you want to install XMRig, choose the first variant,
Enter your Monero Wallet address.
Choose your pool.
After everything is set up, open 'C:/Users/YourUserName/xmrig/xmrig.exe'
Keep in mind that xmriginst.py is now abandoned: use linux_xmriginst.py and windows_xmriginst.py instead!