- Be a practicing member of the Catholic faith.
- Be single and without dependent kids. Nuns cannot be married. They can be widows. They may be considered if they have released marriage bonds through an annulment - but that will be up to the religious order whether or not to accept the applicant. Woman with dependent children are also not considered.
- Be in good health and financial standing. Prior to becoming a nun you will undergo several stages, which includes, Candidacy, Postulancy, and Novitiate period. During this time you will become immersed in the religious community. In all, these stages last about 3.5 years. You will want to be in good financial order - ideally debt free. This may be a requirement of the religious order you are joining. And you’ll want to be in good health. A nun is responsible for their own psychological, dental and physical health until they take their final permanent vows.
- This is more a suggestion than a requirement, but don’t wait until you’re too old. It used to be that you had to be young, but these days there’s a little more leniency regarding age. Regardless, check with your prospective religious order if you are over the age of forty, for some that is the age cut-off.
- Bring experience/education to the table. It is not a requirement to have a college degree or professional experience, but both are considered very desirable.
A Nun’s Life Ministry: How to Become a Catholic Nun
Hubpages: How to be a nun