You add marker points to mark a specific frame of a video clip in a timeline. Marker points mark the beginning of the specific scenes and sequences, they also let the viewer skip forward or back through a clip.
Here is where it is located in vooPlayer:
Once you select the Marker points you will see next screen with the details and options of possible selection
You can fill out the Title, specific time of the markers and choose the color you would like your markers to be.