Decide where you would like your timeshare to be. Consider price and style of timeshare as well as location.
Think about how often you plan to use your timeshare. If you don't really want to take a vacation in the location of your timeshare every single year, it may be advantageous to pick popular, high traffic areas, such as tropical beach resorts or well liked ski ranges; this will allow you greater brokerage power when selling or renting your timeshare.
Think about in what type of place you want your timeshare to be located. For example, Orlando, Florida is a popular destination for families with younger children because of the close proximity to Disneyworld and Universal Studios. Las Vegas is a popular destination for older couples or families with older children.
Choose an actual timeshare destination at the location you've selected. Compare management companies, talk to other owners and ask about things such as annual fees and basic maintenance and upkeep responsibilities.
Decide whether you'd like to buy into a deed or a points system. A deed will give you ownership for a specific weekly block of time; a points system will allow you to break that up into shorter periods of time.