Your Age: The earlier you start the higher should be your Sum Insured as the number of years left would require a greater safety net.
Your Life stage: Based on the life stage you are in, for instance, if you are going to get married or start a family etc, your Sum Insured should factor in the healthcare expenses associated with it.
Health Conditions: If you have a history of medical conditions in your family, your Sum Insured should factor in the possibility of an unforeseen health condition in the future
Dependents in the Family: If you are planning to take a family floater policy with your family members, the sum insured should consider each member's needs and future healthcare expenses for them.
Lifestyle and Personal Habits: An individual's job type, eating habits, stress levels, and other personal habits can affect their future healthcare needs. These should also be considered when choosing a sum insured.