First you decide on what the playing area will be. Choose one of the predefined rectangular layouts...
Or create one of your own, either contiguous or not
If your layout consists of fewer than 60 squares, you may choose which of the 12 pieces you want to use, or allow any to be used
Optionally you may let the computer exhaustively find all the solutions
You may manually try to solve your puzzle
You can get a hint, or be told whether a solution is possible given the pieces you've already placed, or even be shown any of the solutions
And you can generate .bmp files of some or all of the solutions for printing, email, etc.
