First, build a few more billboards near the repair shop and attach a few obvious guidance signs. Most drivers passing by will notice whether there is a repair shop nearby. If your team is skilled enough, you will quickly gain popularity.
Second, employees are required to provide good services. Business is built slowly, and there is no requirement to earn too much at the beginning. Every repairman has a company business card, and the accumulation of repeat customers is very important.
Third, when running any business now, the Internet is very important. Try to publish company information, including contact information, address, and business scope, on popular websites in your area.
Fourth, contact nearby auto parts stores. They also have their own customers. Let customers know about your company through them.
I believe that if you do the above points, your business will slowly become prosperous!