If you have a premium account, you can add multiple business locations and send review requests on behalf of a specific location. This video shows you how to add locations and assign specific review links to those locations.
Always ask the customer at the end of the job: "Would you mind if I send you a request for feedback on how I did today?".
Be sure to spell your customers name correctly and with the correct capitalization (IE. Susan Geoffrey NOT susan jeffrey).
Sending your review request as soon as possible while the great experience is still fresh in the customers mind.