If you have a shy LO, how do you work on social skills with them?

We had conferences with LO's teachers two weeks ago and they said she has really come a long way this year with her social/emotional skills but that she could use a little extra help still. I'm not really sure how to go about this as I think a lot of it is her personality. I was the same exact way as a kid, and that didn't change until after high school.

For example, the teachers showed us a video of all the kids dancing and my LO was just watching. She is way different at home than she is at school, she will sing and dance and go crazy. So, as mentioned above, just like me, I think it comes down more to personality.

Any advice?