This always confuses me. Where do you turn your wheels when parking uphill/downhill? The presence of the curb just gets more confusing.
After some research, the key is simply this. Imagine your hand brake fails and your car rolls down, just make sure it rolls to the side but not into the road.
Assuming your are parking on the right side of the road (in America), here is where to turn your wheels:
|Parking on the right side||Curb||No Curb|
Similarly, while parking on the left side:
|Parking on the left side||Curb||No Curb|