This design, while not very common, is pretty quickly done.
Here’s how to do this unique halo:
Complete the steps to positioning a halo, including the optional third step. The square drawn in that third step is the outer border of your halo.
Illustration of step 2 Lightly draw lines going diagonally inwards from the corners of the outer square. These lines should all be the same length; they are there to guide you in drawing another square.
Illustration of step 3 Connect the ends of those lines to give your square halo its inner border.