Learn Hardcore Japanese: miti ni mayowanai you ni, eki no annaizyo de tizu wo moraimasu. - So that I don't get lost, I get a map at the station information desk.

Breakdown of michi ni mayowanai you ni, eki no annaijo de chizu o moraimasu.

What does ように mean here?

Here, ように means so that or in order that.

It is often used when the goal is a resulting state rather than a direct action you can fully control.

Why is it 迷わないように and not 迷うように?

Because the goal is not getting lost.

So:

Japanese often expresses purpose by stating the desired outcome, even if that outcome is negative in form.

Why is ように used instead of ために?

Both can relate to purpose, but ように is especially common when the purpose is:

Since getting lost is not usually a deliberate action, 迷わないように sounds very natural.

Compare:

In this sentence, ように is the more natural choice.