What are the best practices for the headlines of Google Responsive Search Ads?

Since one of the primary and critical parts of responsive ads is the headline, you must use best practices to make it best for high ROI. For example, the headlines should have targeted keywords, the solutions you’re providing, a proper order to make sense, and different lengths of characters (don’t use the allowed maximum limit of characters always). Most importantly, a headline should have variations like different CTAs. In addition, pinning the headlines can assist you in keeping the headline in a fixed position (if you want).