We (a bunch of SUCKers
www.facebook.com/groups/sydneyunicrazykiters ) were planning on going snowkiting this weekend but eventually decided to stay in Sydney and enjoy the southerly as all the snow melted last week.
In NSW Thredbo is the way to go, taking the Kociuszko Express chairlift then Karells T-Bar to reach the top, then reach the northern side and walk up a bit to reach that big flat area.
Smaller kite size are preferred as you need very little power to start moving on the snow and you can reach high speed easily. But then it's also easier to edge hard so you can handle quite a lot of power, so depend on your level and experience.
Thing is weather can change quickly in the mountains, and wind is usually super gusty because of the landscape. Also be careful if it gets foggy, being out of the resort it's easy to get lost if everything turns white and you can't even see your buddies' kite 20m away.
As for the feet, skis are a good choice make it easier to go uphill and move around when the wind is light. Snowboard is a bit more hassle but more kitesurf-like feeling and great for jumps and tricks.
Enjoy!