The only 4 things you need to know about Illustrator:
The difference between the Hollow and the Solid Arrow. When in doubt, use the Hollow Arrow, and learn to use the Alt/Option key to extend functionality
How to use the Pen tool (see demo) Select the Hollow Arrow tool prior to using the Pen tool
The Layer palette is not optional. Rename your objects and groups. Use the Layer palette to rearrange, lock, and select objects and groups.
The Appearance palette is more important than you think! Think of it as a mini Layer Palette for objects and groups.
Illustrator isn't as tough as it seems but it is different from other programs. Depending on what you're most comfortable with, consider
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