This picture has all pairs of dominoes in it, one of each, find it all.
There are more than one solution. If you look at the setup of the table, the top and bottom are symmetric (the numbers are meaningless). Solve the top part, and you've solved the bottom. The middle part is automatically ordered properly. If you want to get fancy, try and create staggered pairings, or pairings that go from one section to the next.