Let's look at your site the way most of your visitors actually do: on a phone. Phone in one hand, this audit in the other. Work through each section, mark what you find, and leave with a clear action list.
Can your visitors read everything without pinching to zoom?
Can your visitors find their way around easily on a phone?
Can your visitors find service times, address, and contact within 2 taps?
Does the site load fast enough on mobile data?
Are buttons and forms easy to use with a thumb?