You press the board icon in the comment box (all the way to the left)
You press the third option (create puzzle) and press next.
You press start with an empty/blank board
You set up the position where the puzzle will start
You enter the solution
You put the finishing touches on by following the instructions
When you finish, a board icon will appear in the comment box
You post the comment, and you are done!
How would one go about creating a chess puzzle to share (i.e. 5 moves to mate)?