Click on make a block at the bottom of the Variables palette
(or right-click or control-click on the scripting area background and choose "make a block").
This will open up the Make a block dialog box. There are several
steps that you'll do here, corresponding to each
area of the dialog.
Now, you get to choose which tab the block should go into.
Our block is going to draw a square, so let us choose Motion.
The Motion tab should highlight in blue once selected.
(Note: A very common mistake is to omit this step. If you do forget,
your block will become a gray Other block, in the Variables palette.)
Now, you'll want to enter a title for the block in the edit field.
Type draw square, which should show up as in the picture below.
You have the option of making blocks of different shapes,
corresponding to the Command, Reporter,
and Predicate icons. By default the Command icon is
selected, and this is the one you want. (You will learn about
the other shapes of custom blocks soon).
There are two radio buttons that you can safely ignore. You will
almost always want to keep for all sprites selected in this course.
Finally, click OK.
After you click OK, a dialog titled Block Editor
will appear.
Inside the dialog
you will see a specially shaped block with the title of the
custom block that you are creating. This kind of block is
called a "hat" block, and it indicates a starting place for the
draw square script.
You can treat this dialog like you do the scripting area of the main Snap! window. Drag blocks here from the palette to define the script that will run when your custom block is used.
Use the blocks from the Control and Motion palettes to create a script that draws a square, as shown below.
When you click OK, you should be able to use this block as if it
were a regular block. Since you created the block as a Motion
block, it will end up at the bottom of the Motion tab.
