There is no single way to wind a motor that is "best". There are many variations. I don't mean to say that I know them, or that I understand each versions benefits and drawbacks, but...I know enough that I would only copy an existing successful design that matched the size and job that I wanted to motor to accomplish.
Halbach arrays exist and they do work, but, they make the permanent magnet array as a whole have fewer magnetic fields, so...why would you want that? Do you want a high pole-count motor, or a low pole-count motor, and why?
To answer your question, there is a strong magnetic field side on a Halbach array, and a weak side. The strong side needs to face the stator (which is populated with electromagnets that can be turned on and off). On an inrunner, the strong side of the Halbach array on the central rotor needs to face outwards, away from the axle. On an outrunner, the stator is in the middle and the rotor is on the outer rim, so...the strong side of the Halbach array on the rotor must face inwards, towards the axle.
There are several threads about rewinding motors, search for those in the motor section stickey...
https://endless-sphere.com/forums/viewtopic.php?f=30&t=69684