Feeling chatty? Great, head on over to Chat:
To get started tap the big pink button and then select 'New Chat'.
If you can see the person you want to chat with just tap on their name of profile picture and then tap the big pink ✓ to get chatting with them.
Just start typing the person's name into the search bar and when you've found them tap on them, and then tap the big pink tick to start the conversation.
And that's it - get chatting.