Build a mobile able to reach the pink zone. For this you have to combine colored wheels, joining them with connectors. There's 3 kind of wheels: the yellow turn in a sense, the pink in the other, and the blues do it depending on external impulses. There's 2 types of connectors: water connectors can cross other objects, wood connectors collide, bounce or push others, but never cross them. The game includes a very detailed tutorial that will guide you step by step.
Click on the tool you want to use, then click at the points where you want to use it. For example, click on the pink wheel tool and then click at a point to place it there. Or click at the water connector and then click at the two sides you want to connect (usually, a point over a wheel and other point over another wheel). The game includes a detailed and easy to learn tuturial that will guide you step by step.