Map with Popup but hide on load

Dear,

I have create a map File like he following example:
http://dev.openlayers.org/examples/osm-marker-popup.html

german HowTo:
http://wiki.openstreetmap.org/wiki/DE:Karte_in_Webseite_einbinden

But my problem is: I want to have multiple markers and the popups should be hidden until the user click to the marker.
How I can configure that?

best regards, Daniel