The MySQL sys schema is installed by default on MySQL versions 5.7.7 or later. Only users of MySQL versions earlier than 5.7.7 need to install it.
You can install the schema by running the following commands from the system running MySQL:
git clone https://github.com/mysql/mysql-sys.git
cd mysql-sys/
mysql -u root -p < ./sys_56.sql
Note: If using MySQL 5.7, replace the ./sys_56.sql file name in the final command with ./sys_57.sql.