Decide where you would most like to travel. This may include a specific city or country and be either domestic or international.
Research the travel and tourism boards for the specific location you have chosen. You can find these by searching the name of the place followed by "tourism" in a web-based search engine. Sign up for any email listserv on the tourism website, which may notify you of current events and travel deals for the location.
Determine if you have a preferred company you wish to use when making your travel plans. Does a specific airline fly to this location from an airport near you? Is there a resort you have your eye on where you specifically wish to stay?
Subscribe to emails and newsletters for these airlines and resorts. Often these companies send out notices of last minute travel deals that you can take advantage of. This can occur when they are trying to fill empty seats on a flight or rooms at a hotel within the next week or two.
Sign up for a Twitter account and follow airlines, hotels and city tourism boards. Many, such as JetBlue Airlines, announce last second deals you can then book through their website.
Search travel websites daily that focus on last second travel deals. Travelzoo and Travelocity offer announcements and leads regarding last second travel deals to popular destinations such as Las Vegas and the Caribbean. Subscribe to their emails to get regular updates.