In the top-right corner, click on the Loop Messaging icon and you will be redirected to your Messaging Inbox;
Towards the top-left corner of the messaging page you will find the compose icon . You can either click on it and select one of your Network contacts (that is a set composed of your Followers , the users you are currently Following and your
Co-Authors) or resume one of the previous conversations from the left side panel.
See example below:
Note: Messages are reloaded each time the page is refreshed. If you are waiting for a response from another user, refresh your page to see the latest messages.