All you need to do is approach a CM at the monorail station boarding area, and ask. If you are the first to ask for the next, incoming monorail... then up to 4 persons can ride up front with the pilot. They sometimes (but not always) will give you an honorary monorail pilot's license when you unload.
We are always so surprised that so few people seem to be aware of this option (even after they have witnessed families unloading from the front). We rode up front c. 4 times during our recent trip--several times there were other people already standing at the station when we walked up, but no one else had yet asked to ride up front. I think there was only one time all week that we asked, and were told another family was already waiting.
Best monorail trip to ride up front f(IMHO) is the EPCOT line going into EPCOT from the TTC. The incoming monorail track loops around through the EPCOT park before stopping at the station outside of the gates--it provides for some lovely views, especially during the Flower & Garden Fest.