At that age, just being there and talking to her is more than enough. As she gets older, get her out into different environments, just to experience it. Leaves moving in the breeze is waaaaaay fascinating.
You don't have to *do* anything, really. Just interact with her and expose her to different stimuli - things to look at, things to touch, things to taste. That's it. You dont' need fancy classes or special toys or organised activities. Kids love doing things with mum, so you can just work it into your routine (when she's older I mean), so they cook with you, clean with you, go to the toilet with you, etc, etc.
Getting out to mums groups, ABA or playgroup can be a great way for you to get much needed adult time