If you’re new to plushie-making, one of the best introductions is Carolyn Vosburg Hall. She starts with felt toys, small enough to easily hand-sew, and moves up into Beanie Baby size—even if you use good-quality wool felt, the quantities are small enough that it’s very inexpensive to practice with.
There are fifty-two(!) different animals in the book, organized by the concepts they introduce. She covers basic construction, simple thread and button joints, color changes, surface decoration, stuffings, armatures, and finally a variety of fabrics including simple faux-fur bean-bag animals.
Along the way, there are so many different shapes of animals that it’s an accidental lesson in pattern drafting. It had a significant influence on my early experimentation, and also resulted in one of my first Open Source Sewing patterns: a felt ferret.
As a bonus, here’s the pattern; track down a copy of Sewing Tiny Toys in your library or on Amazon (affiliate link) for full instructions.