First, open Squeak and enter a Morphic Project. To do this, click on a clean area. In the menu, select open / morphic project. Click on the new project to enter.
Click on a clean area to open a menu. Select new morph / Basic / CurveMorph. Click on a clean area to drop the curve. Now command-click (i.e. alt-click) on the curve. The set of colored circles that appear are called "the halo". Each handle (circle) has a function. Click on the red one to open a menu on the curveMorph. Select open poligon. Now, you have a Spline. You can play with the handles (the yellow circles and the green triangles) to shape it. Experiment with the other menu options and halo handlers.
Now add a FishEyeMorph, found in new morph / Demo. Place it anywhere. Move the mouse pointer and see though the eye of a fish!
If your Squeak setup soupports sound output, you can try the EnvelopeEditorMorph. Open a world menu. Select from alphabetical list / E - F / EnvelopeEditorMorph. Place it somewhere. Click on the piano keyboard. A note will sound. Now try modifying the sound by dragging the handles of the envelopes.
If your Squeak setup supports audio input (for example on the Mac, on Windows or OS/2), try the SpectrumAnalyzerMorph. Open a world menu. Select from alphabetical list / S - S / SpectrumAnalyzerMorph, and place it somewhere. Click on Start and start singing on your microphone. The sound spectrum is displayed in real time.
Try the other halo handlers, and try the different menu options. Try other morphs also. If you know Smalltalk, from the halo you can inspect a morph, or browse its class. There are many other things you can do. If there is something that you don't understand, don't worry. There are a lot of morphs in the system and some of them are a bit tricky. But you don't need to know them all, what you need is to know the basic ones, how they work, and how you can create new morphs of your own.
To delete a morph, click on the pink halo handler.