Final answer:
To ensure that a curl holds firmly, it should be set correctly. This may involve the use of tools like curling irons or hot rollers, along with hair products such as curl setting sprays, mousses and hairspray.
Step-by-step explanation:
The subject of this question refers to hair styling and specifically the process of curling hair. To ensure that the curl holds firmly, it should be set correctly. Proper setting of curls usually involve heating the hair using curling irons or hot rollers, then allowing the hair to cool and set in curled form. Applying hair products like curl setting sprays or mousse before curling also helps to ensure the curls hold for longer durations. Also, setting the curls in place with hairspray after curling can also assist in making the curls hold firmly.
Learn more about Hair curling