First of all, boot your Arch Linux live CD.
You'll need an active internet connection to use the script, if you need to use Wi-Fi type iwctl to find your Wi-Fi network and connect to it.
You'll also probably want to load the brazilian keyboard layout:
loadkeys br-abnt2
Then, proceed to download the script and run it:
curl -L https://git.io/tali | bash
If for some reason you'd like to clone a specific branch and run that version of the script, you can instead use:
curl -L https://git.io/tali | bash -s BRANCH_NAME
If you'd like to see contents of the script you're about to execute, you can use:
curl -L https://git.io/tali | less