Adapted from ehow.com.

Step One
First determine if all classmates are invited, or only the ones who actually graduated with the class. Also decide if you want to invite faculty and contact the school to make arrangements as soon as possible to include them.

Step Two
Contact your old high school to find out if you had a class sponsor who can assist with anything. Most schools will be able to provide a list of last known addresses for your class year.

Step Three
Find classmates: Use your old yearbooks to create a list of all the classmates. Use CalSDAlumni.com to contact as many alumni as you can. Another good approach is to use whitepPages.com for last known addresses/phone numbers. Call the parents of classmates for current contact information. Some classmates may be on Facebook or MySpace.

Step Four
Pick a date: A very common date is the Saturday of Thanksgiving weekend. Many people still come "home" for the holiday but aren't over-scheduled like they are around Christmas. Summer is also a nice time for an outdoor event, but attendance is greatly affected by vacations and many don't want to spend money traveling home just for a reunion.

Contact everyone you can reach once the date is set so they can mark it on their calendars while you work out the other details.

Step Five
Contact local businesses for cash donations, venue discounts, floral/food donations, and anything else you can get. Use cash donations to off set the price of tickets. Offer businesses an opportunity to advertise at the event. Many reunions now create small "memory books" with current info about each alum, and you can add a business ad section in the back of the book.

Step Six
Pick a venue and explain you are planning a reunion on a limited budget. Just as venues charge more for weddings, they charge LESS for reunions, especially if you choose Thanksgiving weekend because it is difficult to book other events. Any revenue for them is good revenue.

Before setting an individual ticket price, include any price that applies: meal cost per person, hors d'ouevres, bar, bartender fees, DJ or other entertainment, security personnel, room rental, linen fees, state and city taxes, and gratuity (18%-20% is acceptable and some venues will include it in the costs). Don't forget to include cost of decorations, flowers, a memory book or a program, invitations (printing and mailing), and surveys. Once you have a total if you had to estimate a few costs add a little wiggle room, divide by the number of people you believe will attend and set that as the ticket price.

How many will attend? If you contact enough people in advance and give them the date ASAP, ask them to notify you if they are planning to attend, and if they plan to bring a date. Poorly planned or late planned reunions often see just 20% of their class attend. Small classes however will sometimes see 100% attendance. Try to get a count of the maybes well in advance, and make sure ticket prices regardless of attendance will at least cover the flat fees for a DJ/Floors/room rental.
7Step SevenIf you can send evites, you will save money on printing and postage, and everyone can see who is attending or not attending. Otherwise, you can print invitations as places like Kinkos; if you are lucky, they will even help with a little bit of the design.

Include in the RSVP questions about choice of dinner (if there is a choice), their guest's name and dinner choice, their contact information including phone and email, and where they should make payments. The invitation should include information of the venue address, start/end time of the event, a brief summary of the program if there is one, who to contact if they have questions, and a list of local hotels where they can stay if coming from out of town.

Tips & Warnings
* If many people are traveling for the reunion, ask a few local hotels to save a block of rooms and rent them at a discount.

* Disperse assignments to volunteers based on whether they live locally or not. Local volunteers can contact businesses in person, non-local volunteers can search the internet and the phone book for old classmates.

* Many people who dropped-out or were held back still feel like a part of a certain class year. Consider this when searching for classmates and decide if you would like to include them.

* Don't try to go it alone! Request help from the start so that you don't get bogged down trying to find people, plan the details, and live your own life.

* Don't stress the negative reactions! Sadly, not everyone has recovered from the traumas of high-school politics -- and some of those politics may still continue with some classmates. No matter how you plan the event they will disapprove of the venue/date/cost. Try to keep it affordable and convenient as everyone will be at different crossroads in their lives, but remember that you cannot plan around everyone's schedules and budgets.