Create a CSV file with two columns (no column headers):
One column containing the distinct_id values of the users you want in the cohort
One column containing a user property value that identifies cohort membership (e.g., inCohort == "yes")
Example structure:
user_abc123,yes
user_def456,yes
user_ghi789,yes
โ ๏ธ Do not include column headers in the CSV โ you'll define them during the upload wizard in the UI.