You should rotate the tiles to connect all of them to form one component, but without a cycle.
You can use the level button to toggle "Stay on the same level" to enjoy randomly generated patterns of the same level, or advance to more challenging levels. All levels are randomly generated which means that each time you play, you get a new pattern.
In some cases, there are more than one solution; only one is accepted. Use the hint button to solve a tile for you. Use the hint button carefully as the number of hints is limited per level.