Need help setting up my group

I have created a group, Savvy Sisters.  I thought I did it correct but no body can join.  I sent messages to all my savvy sisters but they still can't.  I thought they could join.  Another thing I wanted to do was send a message on the chat line but I could not find where to start a new thread. 

I have never had so much trouble before. I have computer experience but no I.T. experience and I'm beginning to think that is what I need to set up a group.  I can't even find any instructions for help.

Is there a step by step guide to help me get this group started.  Also to keep it going.

Debbie