It's never too late to go back to schoolPlay Video
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Many adults are banking on going back to school as a way to get a leg up in the job market.
Nearly 4 million people age 35 and older are enrolled in a degree-granting institution, according to the National Center for Education Statistics. More than two-thirds are women.
Despite a slack job market, many may hope an advanced degree or new credential will make them more "marketable"—helping them find work in a new field, land a higher-paid position, or simply hold onto the job they have in an increasingly competitive environment.
But is going back to school worth it? It can be.
(Read more: Questions to help protect your retirement savings)
Determine your professional goal, what experience is needed to get there, as well as the overall educational costs.
Dani Babb, a professor and author of "The Adult Student: An Insider's Guide to Going Back to School," said whether it is necessary to go back to school will also depend on the type of program and school you choose. "College is not necessarily [the] best choice if the career you go into won't pay back the debt that you'd incur. It might make more sense to go to community college or enroll in an online program," she said.
Choose the most affordable college, university, or professional school—whether a traditional or online program. Keep in mind you may need to be enrolled at least "half-time" to receive financial aid. There also may be some restrictions. Some financial aid, including grants and scholarships, may be limited to those pursuing their first bachelor's degree. That said, you don't necessarily have to rely solely on loans.
(Read more: What you should be asking your financial advisor)
Take these steps to help find money to go back to school:
1. Fill out the FAFSA form
Most schools still require completion of the Free Application for Federal Student Aid (FAFSA) to help them determine how much aid is needed and how that aid should be packaged. The FAFSA is used to calculate the expected family contribution, which is a measure of your ability to pay.
The school will take your contribution and subtract that from the cost of attendance to determine your financial need. The financial aid package you get from your school is based on your financial need.
2. Contact the institution's financial aid office
Check immediately with the financial aid office at the institution where you plan to enroll in to find out what grants or scholarships may be available. The FAFSA may be required for application.
(Read more: Retiring with more: Don't wing it on your 401(k))
Financial aid is not limited to bachelor's and advanced degree programs. You may find the cosmetology or culinary school that you are considering offers grants and scholarships as well.
3. Search for 'free money' using online scholarship sites
Whether you've been out of school a few years or a few decades, you can look for free money from national and local scholarship programs.
Go to scholarship websites, including StudentScholarshipSearch.com, Fastweb.com or Scholarships.com to find scholarships for your field or that match a unique characteristic about you. Also check out ScholarshipPoints.com, which is like a frequent guest program for scholarships. Students earn points by engaging in various activities like completing surveys or searching for scholarships and can use those points to enter drawings for scholarships.
4. Don't overborrow
Follow this rule of thumb: Your total student loan debt at graduation, including debt from pervious loans, should be less than your annual starting salary, said Mark Kantrowitz, senior vice president and publisher of Edvisors.com. "If total debt is less than annual income, you should be able to repay your student loans in 10 years or less," he said.
But empty-nesters take note: You don't want to be paying back loans after you retire. If retirement will be less than 10 years away after you graduate, you should borrow less.
5. Explore other ways to educate yourself
Finally, make certain that certification or an advanced degree is actually needed for the position that you are trying to attain.
"There may be other ways that the marketability that an advanced degree gives you can be replicated," said career coach Caroline Ceniza-Levine of SixFigureStart. Instead of attending a "brand-name" college or university or getting that "brand-name" credential, focus on landing a "brand-name client," said Ceniza-Levine.
You may gain the knowledge you need for your next career through massive open online courses on websites such as Udemy.com or Skillshare.com or by auditing community college classes than enrolling in a part-time or full-time program.