Please follow below steps:
Connect your device and projector to the same Wi-Fi network.
2. On projector, go to Home > Screen Mirroring, there is projector's device name shown at the upper right
location. (e.g. "ViewSonic PJ-XXXX")
3.On your phone/tablet, do the following:
iOS:
Access the drop down control menu.
Select the “Screen Mirroring” icon.
Choose “ViewSonic PJ-XXXX”.
Android:
Download and install the “Google Home” application and open it.
Pull-to-refresh the app and wait for 1 minute.
“ViewSonic PJ-XXXX” will now be visible, select it.
Choose “Cast my screen”à”cast screen”à“Start Now”.