"How do we choose who we want elected into the House of Representatives in comparison to those that we want in the Senate? "

Thanks for your question, Kaihla! At federal elections, Australians choose members of parliament to represent their views and interests in the House of Representatives and the Senate.There are 150 members elected to the House of Representatives — one for each of Australia's 150 electorates. An average of 100 000 voters live in each electorate.  

Each member is elected using a system of preferential voting, designed to elect a single member with an absolute majority for each electorate.

In the Senate, twelve senators are elected to represent each state and two senators are elected to represent each territory. State senators are elected for a period of six years using a system of rotation that ensures that only half the state senators end their term every three years. Territory senators are elected for a period of three years at the same time as the members of the House of Representatives.

Senators are elected using a system of proportional voting, designed to allocate seats to candidates in proportion to the votes cast in an election.

For further information about voting see the Australian Electoral Commission website.

diagram to help explain How do we choose who we want elected into the House of Representatives in comparison to those that we want in the Senate?