Arrow heads and connection symbols
There are different styles of arrow heads, which also include diamonds, circles and other notations used in UML diagrams, electrical diagrams and more.
Select your connector, then look in the format panel on the right – there is a huge list of connection styles or arrows you can use for both the start and the end of your connector. Choose an arrow or connection symbol from the start and end drop-down lists.
Alternatively, you can use the connector shapes (with arrows attached) from the General or Misc shape libraries in the left pane.
Once you have chosen a certain style, when you draw a new connector, it will use that style.