Draw the Lewis structure
Determine the molecular geometry
Check for polar bonds
See whether the bond dipoles cancel
If the shape is symmetrical and the outer atoms are the same, it is usually nonpolar
If the shape is asymmetrical or has lone pairs that create an uneven shape, it is usually polar
If the molecule has different atoms arranged unevenly, it is usually polar
If the molecule has identical atoms arranged evenly, it is usually nonpolar
If the central atom has lone pairs that affect the shape, it is often polar
If the molecule has a net dipole moment, it is polar
If the molecule has no net dipole moment, it is nonpolar