Select an agency that has experience, customer reviews, effective communication, and case studies. An effective digital marketing agency in Delhi should be able to understand what your business goals are, create specific strategies and provide you with regular reports on the performance of the strategies. Test their proficiency with SEO, PPC, social media, content marketing and website optimization. A good agency with a positive reputation and ethics in marketing can assist you in making your website more visible, attract quality leads to your site and build a business that will grow over the years.