You can explore whether you are dominant or submissive by noticing which power role excites you in fantasy, which feels natural in negotiation, and which you want to try in practice. Many people discover they are a switch, and some find their preference changes with different partners.
Discovering whether you are dominant, submissive, or a switch is an exploratory process rather than a test with a definitive answer. Several questions help clarify the preference. What role do you take in sexual fantasies? Do you imagine directing the scene or being directed? What excites you about BDSM: power, protection, service, surrender, control, trust, physical sensation? Which feels more natural when you read or watch BDSM content? Many people find that the answer becomes clear only after real experience, and some discover that their preference shifts with different partners. It is also common to feel drawn to both roles, which points toward switching. The choice is not permanent; a person who starts as a submissive may later explore dominance, or vice versa. The process of self-discovery often involves reading, attending educational workshops, talking with experienced practitioners at munches, and trying light versions of activities before committing to more intense play. A partner who pressures you toward one role is not helping you find your authentic preference.