This is very simple and quick.
In any window where both the request and the employee are shown (day, week, availability etc):
Either: Select the relevant shift request and right mouse click on the employee's name
Or Select the relevant employee and right mouse click on the shift request
In both cases there will be a pop up menu with at least two items:
The shift details.
Close
Click on the shift details - a note will automatically be added to the requirement saying the user has contacted the employee about that shift type and location.
To see this information automatically:
Ensure you have the likes and dislikes columns displayed on the request / requirements list.
When you click on the employees name, a phone symbol will appear in the likes / dislikes column for all requests the employee has been contacted about. (i.e had the above notes added)
Hovering over the phone symbol will give more detailed information: when and who contacted them.