When you arrive on the roof you will find that the Questar has already been set-up for you on wooden desk-like pedestals.  All necessary alignment of the telescope has already been done and the telescope is now "Ready for viewing".  The above image shows the telescope with its lens cover removed and the correcting lens exposed.  You should NEVER under any circumstances touch or attempt to clean the correcting lens (or any other lens in the Questar, including the eyepiece).  The optics in the Questar are of very high quality and even the smallest scratch or smudge of oil can ruin your evening of star gazing and possibly permanently damage the telescope.