Attend university. Although it is not always necessary, a degree in Theology or Divinity looks good on your resume, and will help you when you're looking for work. You may also wish to continue on to graduate school in a master's program. As many position require chaplains to provide pastoral guidance to students of many different faiths, it will help to educate yourself in several different theologies.
Become ordained. Most chaplaincy jobs will require you to become an official member of your faith's clergy. This may require going to a seminary or rabbinical school, or to an Islamic school that trains Imams. These schools will train you in how to be a religious leader, and will provide you with opportunities to develop your skills.
Work as a part of your clergy. After graduating from a religious school, you should begin looking for work. You may be able to find chaplaincy jobs without prior experience, but many will look favorably upon time spent working in a mosque, synagogue or church.
Search for a job as a university chaplain. Many religious schools have their own job boards, but you can also use regular job search websites as well as the careers page of university websites.
Prepare your resume with your qualifications and experiences, and apply for a chaplaincy job that appeals to you. Wait for a university or college to contact you for an interview.