Specific, Measurable, Attainable, Relevant, Time-based.
Source: https://www.tide.co/blog/business-tips/how-to-create-a-business-plan/
Main questions before designing your business plan:
1. What would you like do?
2. Do you think your business idea fits the needs of future clients?
Observe the market, do your research! If possible, test your idea before starting (i.e. short questionnaires submitted to specific social media groups)
3. Do you have the specific skills and competencies to run this business?
Learn about the specificities of your future business, attend trainings and obtain the most important qualifications needed
4. What are the pros & cons of starting your own business?
5. What would be the main challenges/obstacles you think you will face?
6. How would you respond to these challenges?
7. Do you have a plan B?
Based on the answers provided, you can now start to define a SMART business plan.