Checklists are used to walk an employee or payroll administrator through a specific company process. This could be something like new hire orientation or termination of a previous employee. 

Navigate to Team > Hr > Checklists > Checklists. 

Click Assign New in upper right hand corner.

This will open the Assign New Checklist box. This box is where you can select employee(s) and specific checklist.  First in the Employee(s) drop down box select Browse...

Next using the checklist drop down, select the checklist you would like to assign to the employee(s).