I downloaded the most recent release from the Sass Github releases page and extracted the files.
$ wget -O dart-sass.tar.gz /
https://github.com/sass/dart-sass/releases/download/1.22.12/dart-sass-1.22.12-linux-x64.tar.gz \
&& tar xvf dart-sass.tar.gz
Then I moved the extracted files to where I wanted them in the file system.
$ sudo mv dart-sass /opt/
And finally I made a symbolic link to sass from the bin (which my path looks at).
$ sudo ln -s /opt/dart-sass/sass /usr/local/bin/
To check I have sass installed I ran
$ sass --version
1.22.12