Download and install the application from the web. Hit the short cut on your desk, press “later” for the license key step. You will get a screen like below upon hitting the “Open” icon there:

click to enlarge
From the above snap you can see the file types supported by the package. Select the ProE file to open. The important viewing operations you can perform here are: Pan, Zoom and rotate. Apart from that you can take the print outs and send the file as an e-mail attachment. The professional version of the application will allow you to create mark ups, measure distances, create exploded views, check mass properties and enable password protection.