What to pack/get for a trip to Australia?

I'm going to Sydney, Australia in one month to stay with a friend for 10 days and I have been doing a lot of research on what I need to have and bring when traveling over seas but I'm still wondering if there's anything else I need besides the obvious like clothes and shoes etc? For instance do i need a new sim card (i have a iphone 5c)? Or do i need a power converter(i have an adapter) also should I bring my spending money on a card? Basically I need to know everything i should bring that would be helpful or necessary. Anything you can think of will help! Thanks!

Also any tips on traveling internationally will help! Its my first time flying alone and outside of the united states.

Yes, get the convertor and transformer. You will need two sets, one for the carry-on and one for the checked luggage. It is a really good idea to have a USB hub with you.

When buying a CD/DVD be sure it will work in Region One, where the US.is. Our video equipment will only play that kind.

Loop the camera charger though the handle of your carry-on and then plug it in. That way you can't forget it on travel day.

Get some tissues for the trip, the kind I like are the ones that are 3 pkgs for $1, the pocket size. Any bathroom stop may not have TP or even a toilet seat. So be prepared. Wet wipes are great to have too. Easier to use that the antiseptic things in the small bottle.

Of course, you have to get travel sizes on everything. Even if you travel often, it is a good idea to replace these in case they would dry out.

A small notebook and pens are a good idea too. You write what the site is, or the date, and take a picture of it. Then you can sort your photos easier.

When you get to the airline seat, set it up immediately with gum, tissues, snacks, EMPTY water bottle, anything else you want with you.

Take extra SD cards and replace these every couple of days in your camera. Just in case something gets lost or stolen. Make it a habit to set your camera down in the same way every time. So you hook it inside your day bag so it does not become steal-able.