I agree with the above comments regarding the push in the back to ascertain which foot forward.
The problem I find in chatting to most weekend warriors, is that they refer to left foot forward as "natural" and right foot forward as "goofy". The same as in surfing.
This is the wrong way to look at deciding which foot forward as there is no correlation; ie, you stand sideways on a surfboard/skateboard/wakeboard/snowboard etc, and you stand straight with shoulders toward the boat on a slalom ski.
I'm right footed/handed in everything I do, I surf left foot forward (natural) and yet I slalom right foot forward.
Go with the push in the back method, and if someone starts talking about being natural or goofy footed, walk away, they're stupid.