Obviously, you need to be in a trade that needs to be licensed to be able to advertise that. Otherwise you can say you are bonded and insured. If your trade does not require you to be bonded where you are located you can purchase a dishonesty bond. These typically cost around $150 for a $10,000 bond per year.
Pro-Tip- Getting your bond and certificate of insurance laminated is a great tool when you are at a prospective client’s house. You can show them you are a professional that takes pride in their business. It also differentiates you from your competitors. This should lead to more business.