Please see here for information regarding luggage allowances and limits, and check with your airline for what applies to you.
Be sure to pack for the season and your destination’s climate. If you are arriving in Townsville in summer for example, you won’t need warm clothing. If you are arriving in Melbourne in winter however, then warm clothes will be essential.
Remember, you will be able to buy most, if not all the items that you need in Australia, including clothing and household goods.