Write the Drivers Licence number on the back of the cheque. You as the person accepting the cheque should initial the back of the cheque. Do not accept a post dated cheque. Do not HOLD a cheque to a certain date to be then cashed. Do not accept unknown company cheques automatically.
People are under no obligation to accept cheques for payment.
If you are not satisfied that the cheque is legitimate you do not have to accept it. This is an increasing problem due to the accessibility of colour laser and ink jet printers. It is important to get in the habit of checking bills whether large or small denominations. Compare bills to a known genuine bill, and look for the differences. There are a number of security features built into Canadian currencies.