By flight: Mumbai to Bagdogra Airport, then taxi/shared cab to Darjeeling
By flight: Mumbai to Kolkata, then Kolkata to Bagdogra, then taxi/shared cab to Darjeeling
By train: Mumbai to New Jalpaiguri Junction (NJP), then taxi/shared cab/toy train to Darjeeling
By train: Mumbai to Kolkata, then Kolkata to NJP, then taxi/shared cab/toy train to Darjeeling
By road: Mumbai to Darjeeling by car/bus via NH routes, with multiple overnight halts
By air and road: Mumbai to Bagdogra, then road transfer to Darjeeling
By air and rail and road: Mumbai to Kolkata or NJP, then onward to Darjeeling by road
By train and road: Mumbai to Siliguri/NJP, then Darjeeling by road