as a foreign, I start with Pinyin.. then characters.. practicing with native speakers help me to improve my Oral chinese

There is no short cut in learning a language . Do you have elementy knowledge of Mandarin ,if so you can chat me in Chinese ,I would like to help you .

If you don't speak any Chinese then you have to start with the pinyin and learning the Chinese writing system and how to pronounce the tones and gradually emerge from basic simple vocabulary to more intricate sentence forms ,that applies a reversed built system ( compared with English language for example). However if you spoke Cantonese ,then you are already familiar with the characters ,tones and most vocabulary is very similar, so it wouldn't be difficult to depend on yourself to learn it using several assisting tools like the ones mentioned by Eva.

多和母语人士聊天，互相学习，这是一条简便易行的方法。

Italki doesnt work sometimes