Want a free pass to Disney? Here's how.

If you're interested in the "Give a Day, Get a Disney Day" promotion, it's best to take advantage of it early, according to Julie Neal, author of "The Complete Walt Disney World 2010" (Coconut Press, $24.95).

"Many millions visit the Disney theme parks every year, and if you wait until July to volunteer and expect your free day in August, the million slots may be filled," she said.

Here's more you'll need to know if you want to participate in "Give a Day, Get a Disney Day."

To qualify, you'll first need to pre-register and sign up through the website: www.DisneyParks.com.

You must be at least 18 years old to sign up, and children must be at least 6 to participate in the program. Ages 6 to 17 must be accompanied by a parent or guardian when volunteering. Other age restrictions may apply to certain volunteer opportunities.

You may only sign up a maximum of eight members of your household. One ticket per person, regardless of the number of times you volunteer.

You must sign up with a participating organization that's listed on the website. Other volunteer activities do not qualify.

Volunteer service must be verified. Once that's been done, you'll receive e-mail instructions on how to print a voucher you'll redeem for your free theme park ticket. A valid ID will be required at the Will Call ticket window at Walt Disney World or a ticket booth at Disneyland.

The program started Jan. 1 and will continue until all tickets are distributed or until Dec. 15, 2010.

Your voucher for a ticket must be redeemed by Dec. 15 and used on the same day of redemption.

Some black-out dates do apply.

Tickets are not transferrable. Because most vacations are more than one day long, Neal said it's important to look at other ways to save money on a trip to Disney.