Think about who your ideal customers are and work out what is the best way to reach them.
For example, if you’re based in Belfast and want to reach business people locally, you’d be better attending networking events that they go to than trying a scattergun approach of advertising in a newspaper.
Maybe you want to target young mothers who want to get their shape back. Put up posters in local nurseries or primary schools.
Your message needs to be specific to each market, which is another reason why generalist advertising brings such poor results.
Good luck!