Each Domino can be placed once and only once, but they may have to be rotated. It is helpful to first find the pairs of numbers that only appear once in the puzzle, and the make lines between connections that have been made impossible because that domino piece is already in use.
Send your solution to Gail Allen to win 20 beans.
Solving Alte puzzles is usually a sure-fire way to get beans, provided the submitters are offering them, of course. But don't do them for the beans. Do them to get your brain all fired up and stuff.