Draw the Lewis structure
Count electron domains around the central atom
Count each bond as one domain
Count each lone pair as one domain
Determine the steric number
Steric number 2: sp
Steric number 3: sp2
Steric number 4: sp3
Steric number 5: sp3d
Steric number 6: sp3d2
Steric number 7: sp3d3
Check for resonance if needed
Use the hybridization of the atom with the relevant electron domains