Your Idea. It’s not enough to say that you’re going to offer an exercise classes. The people considering your classes will want to know exactly what they are going to get for their money, and it will be up to you to explain it concisely and effectively. Understand that you’re basically giving a sales pitch to potential attendees. You’ll have to really narrow down your topic.
Eckhardt and Shane (2003)  argue that when taking the path of entrepreneurship, one of the most important indictors for future entrepreneurship is the skill of finding the business opportunity. This is seen as the lynchpin around which the promise of entrepreneurial venture is to be built . Shane and Venkataraman state that individuals must possess prior knowledge and the cognitive properties necessary to value such knowledge in order to identify the new opportunity. This normally allows a triggering of the opportunity which can then move forward to scoping and validation.
Search engines remain the top Internet tool for shoppers to research purchases. The Association of National Advertisers states, 75% of U.S. big companies use search engine positioning. For large and small companies optimizing their web pages to provide top listing in search engines such as, Google, represents a task to be outsourced to professionals. The search engine optimization (SEO) field is is growing. The skills required to succeed in this business opportunity, as rated by SeoPros.org are: understanding reciprocal linking, ability to develop keywords, HTML knowledge, and strong language skills.
There’s plenty of work and clients to be found. If you know where to look. To start, you need to know if there is enough demand for your skill to make it worth the effort to go out looking for work. Start by searching for freelance postings on sites like Flexjobs, SolidGigs, Contena, greatcontent or one of the dozens of other skill-specific freelance job boards.
Amazon: Many people don’t realize that Amazon is a haven for third party sellers, including regular Joes and Janes cleaning out their attics and garages. If you plan to sell more than 40 items per month on Amazon, consider registering as a professional seller. You’ll need to pay a $39.99 monthly subscription fee, a referral fee that usually ranges from 6% to 20%, and a $1.35-per-item closing fee for media items. You won’t pay the $0.99-per-item selling fee, however. Alternatively, register as an individual seller. The fee schedule is the same as for professionals, except you do have to pay the selling fee and don’t have to pay the subscription fee.
You could try advertising more, for example, by putting up signs around the neighborhood, posting about it on social media, or having people you know spread the word. You could also try doing it in a different neighborhood that might have friendlier people, or do it in a time and place where there's likely to be a lot of people walking around the area (e.g., near a church before the end of a mass).