Practice, practice, practice!
You can copy somebody else's technique--I tried several and eventually came up with my own--which is usually the ebst way to go about it from what I hear. Unfortunately, I'm still not that good at eyes. It can take a while to settle down on doing a good eye that you like. And, of course, it would help if I did more human eyes than teddy bear eyes! LOL
Here's a link:
The Old Texas Woodcarvers Shop provides wood carving tools, wood carving books & roughouts.
Start by making practice sticks and you'll get more comfortable in making eyes. Search the Internet--or wait for somebody here to give you some more links. You can even search on eyes here--you'll get tons of info. But I would start with making practice sticks, and go from there.
Bob L