There is no direct route from Liverpool, it all goes round in circles.
One way is to get to M4, take Cumberland Hwy exit and follow Old Windsor Road all the way to Windsor, then turn right at the lights at George Street. Follow George St to it's end at Richmond Rd.
Another way is to stay on the M4 until Northern Rd exit (Penrith), follow Northern Rd all the way to Windsor and you emerge on Richmond Road just near the roundabout.
I'd like to see you do that in 30 minutes.

It takes about 20mins from my place at St. Marys, but then I'm the driver who used to drive at 50km before the speed limits where reduced.
I went out there today actually, just to take a look and feed the fish. Must be the first time I've been there and never bought anything.
That last pic is a beautiful fish, I saw some similar today. I was playing a game pretending which fish I was going to pick, and I must have picked about 50! Each time a different one swam by it was "Oooh, look at that one".