What is the most effective method for learning Mandarin? Should one focus on reading, listening, or writing/typing first? Why?

You probable start out see some “character” and can only copy paste or photo and computer translate

So first step is download pinyin keyboard, apply Italian to transliterate speech read each word. Compare

打字

you will have no sense

But in translation

dazi

compile

to

打字

because frequent disyllable

You want further notate in Italian for tone of syllable

dǎzì

dictionary entry or machine translator

Do this for word you need to learn, and develop read sense. This way your read is necessarily Mandarin, whose speech you read in Italian for their “character”

First stage to support listening. You will never know listening on own, without reading. And they do for pedagogue normal school, transcript “character” option “pinyin” when they talk oral for your listen

There is more stage to learn foreign, civil and direct, rather than inferior or liaison, but you need to show you can do this first stage for like 3,000 word first