In the meet
On each profile there is a big heart icon.
In the 'Meet' section of the app you have the option to Like (heart icon), Pass (x icon), Go Back (rewind icon) or use MixHER (mixer icon).
When you tap on a profile you have the the big heart icon to Like them and Add Friend.
You can tap these icons to Like someones profile or add them as a friend.
When you Like and/or Friend someone's profile, it will send them a notification that you have Liked/Friended them and that you're down to chat.
You have to Like or Friend people to start a conversation with them so..... what are you waiting for! Go!