First notebook entry: Introducing myself

First thing I would like to suggest you is to choose the right word to refer yourself, because Indonesian has many of them, ex. Aku, Saya, Gue, Gua, dst. This relates to the emotion and content of the text, wheter you want it to be formal or informal. And it must be used constantly the same for the whole text :)

Hai! :) Nama saya Bec.

Correct!

Umur saya duapuluh dua.

This sentence considered as informal, in a formal manner: Umur saya dua puluh dua tahun. And in Indonesian languange, textual numbering should have space between every words.

Saya tinggal di Melbourne, Australia selama semua hidup saya.

or, you could say seumur hidup saya.

Aku berbicara bahasa Inggris.
Saya bicara dalam Bahasa Inggris.

Saya mau belajar bahasa Indonesia karena teman saya berasal dari Indonesia dan saya mau berkunjung ke Indonesia dengannya.
Dengannya usually used as a starter in the sentence, for this case you can use bersamanya.

Pada waktu luang, saya menikmati menari, menjadi sukarelawan dan menonton film.

That's all!

First notebook entry: Introducing myself

Hai! :) Nama saya Bec. Umur saya duapuluh dua puluh dua (tahun). Saya tinggal di Melbourne, Australia selama semua hidup saya (no need to write "semua hidup saya", but if you really want to, you could replace "semua with "seumur"). Aku berbicara bahasa Inggris (Aku is informal, while saya is formal, choose between the two in a sentence. If you friend comes from Jakarta, you could surprise him/her with "gue", Jakartan slang :D if your friend comes from West Java, you may thought to use "aing", it is a very rude form of "I" :p or "abdi" the humblest form, if he/she comes from Central Java/Yogyakarta, you could use "kulo", a very soft form of "I")

Saya mau (mau tend to be informal, you could use ingin in formal situation) belajar bahasa Indonesia karena teman saya berasal dari Indoesia dan saya mau berkunjung ke Indonesia dengannya (i feel the same with what sanprista post, it is a little confusing)

Pada waktu luang, saya menikmati (menikmati is right, but it feels weird if you say it on daily basis), menari, (menjadi) sukarelawan dan menonton film.

You could also correct my english in this post. While I am relatively fluent in conversational English, I tend to mix the grammar up. Have fun learning english :D I'd be glad to correct your bahasa Indonesia and giving you some tips (using bahasa/bahasa daerah slang :D)

First notebook entry: Introducing myself

Hai! :) Nama saya Bec. Umur saya duapuluh dua puluh dua. Saya tinggal di Melbourne, Australia selama semua hidup saya (no need to write that, but the grammar is right). Aku (for consistency, you should use 'saya', but 'aku' is okay) berbicara bahasa Inggris.

Saya mau belajar bahasa Indonesia karena teman saya berasal dari Indoesia Indonesia dan saya mau berkunjung ke Indonesia dengannya. (it's a little bit confusing, she has been living in Indonesia but you wrote that you will go to Indonesia with her? I suggest: saya mau berkunjung ke Indonesia untuk bertemu dengannya ^^)

Pada waktu luang, saya menikmati ('menikmati' is right but maybe 'suka' is better) menari, sukarelawan dan menonton film.

good job~

it's good to know that you're interested to learn Bahasa ^^