How do i join a Facebook group?

[Lou]

I was invited to join a secret group but i refused but now i changed my mind and want to join. The administrator tried to invite me again but it doesn't seem to work.
It's a secret group so i can't search for it.

[Shoaeb]

just sarch that group nd join

[Nayan]

search that group using facebook search option and join it.

[rjhfocus77]

find a group you want to join and press join

[esystematix]

To join a Facebook group you need to know which niche you want. Then find a group matching your requirements and click on Join group. Then wait until admin approves your joining request.