The sign for trolley is generally going to be the same as the sign for TRAIN.
TRAIN as in: "choo choo" train. (A railway train).
Note: For the sign "TRAIN," both hands are in "H" handshapes (or loose "h" handshapes). The non-dominant hand stays stationary and represents the train tracks. The dominant hand moves forward and back along the tracks.
Trolley: Advanced depiction using "C" handshapes (Classifier "C").
Suppose you were telling a story about a trolley in San Francisco and wanted to say, "then the trolley went up a hill." After establishing that you are talking about a trolley by fingerspelling "T-R-O-L-L-E-Y" and then signing TRAIN, you could then use "C" handshapes to represent the trolley and its movement up the hill.
"Trolley moving up a hill." (Version)
There are other ways to show a trolley's movement. You could use a single palm-down flat hand:
(If you were talking about a double sectioned trolley you could use two palm-down flat hands (one close behind the other).
TROLLEY (version)
Yet another way to sign trolley is to use a bent-V handshape and flip it back and down twice.
This concept is based on the "pull rope" system some busses use to alert the driver that a passenger wants to get off:
Also see: BUS
