Make sure you have everything needed.
The screenshot shows where the controls and functions can be found.
Select the icon at the left bottom of the presentation window. You can now browse for a document on your computer.
More about supported document types.
Select the right bottom icon of the presentation window. A menu bar with drawing controls appears.
Select the webcam icon positioned at the center bottom of the window.
Select the desktop icon positioned at the center bottom of the WebClass screen. Than select "Region" to share a part of your desktop or "Full Screen" to share your entire screen. Please be aware that a larger areas require more bandwidth.
Select someone in the participants window and press "Switch presenter". The selected participant can now share his webcam and take control of the presentation or upload its own Do not forget to unmute the microphone of this person in case you muted it earlier. You can turn yourself back to be the presenter any time you want.
If you type a message in the chat window it can be read by the participants.