Ask at the right moment
Ask right after a job goes well, while the customer is happy. Make it easy: a direct link or QR code, not instructions to search for you.
Ask everyone, honestly
Ask all customers rather than picking only happy ones, and never offer payment or discounts for reviews; platforms prohibit it and it can backfire.
Reply to every review
Thank people for good reviews and respond calmly and helpfully to bad ones. Future customers read the replies too.
Do this today
Make a direct review link and QR code, and ask your last three happy customers.