I believe the answer is don't need. Just start posting and get extra upvote daily. Hope I am right. Else you can check out this post. You have been nominated by @jeanlucsr at the comment side. And at this post, I didn't see that it is mentioned to write a post to accept the adoption. But you can double check.

The post is here

Check this one as well.
https://steemit.com/adoptme/@freewritehouse/you-got-adopted-week-25

Hope this helps.