She set her self-introduction as a pinned Weibo post.
Tips
usage
置顶 (literally 'put-on-top') is the verb 'to pin' — also used for chats: 置顶聊天 (pinned chat). 帖 here is read tiě (3rd tone) in the noun 'post / thread' sense, distinct from 贴 tiē 'to paste'. The forum-post sense traces to BBS-era 贴吧 culture.