To create a new post, navigate to your channel or to the main newsfeed and click the composition field, labelled "Speak your mind", as shown here: 
Alternatively you may click the + button near the top left of any site page, labelled "Compose":
To create a new post, navigate to your channel or to the main newsfeed and click the composition field, labelled "Speak your mind", as shown here:
Alternatively you may click the + button near the top left of any site page, labelled "Compose":