Visit the Disney World website. Sign in with your Disney account or create one. Click on "Where to Eat." The site brings up a list of all of the online booking options with descriptions and the locations of each restaurant. Read through the descriptions and settle on a restaurant or two.
Click on the "Make a Reservation" box on the same page. The box can narrow down the restaurant possibilities by location, cuisine or dining experience, or you can enter a restaurant name. It also has a box to check if you want to only see restaurants in the Disney Dining Plan. That plan is only available to guests staying at a resort hotel.
Insert the date, time and number of guests.
Click the "Search for a Table" box. The site will inform you if seats are available for that day and time. If you want those seats, confirm the purchase and check out.