Your automobile may have a tire out of balance or a worn part in the front end causing this "shimmy" effect .
Steering wheel shakes
Tires out of balance, bent wheel, tire defect, or suspension or steering parts worn.
Warped rotors
could be bad alignment
allignment
1 of 2 things or both, alignment or balance.
Tire out of balance or bent wheel.
I have seen this with bad or unbalanced tires.
It could be wheel balance or worn out steering joints. Have it checked by a trusted garage soon!
Could be that the steering wheel rubber bushing is worn or lose. This bushing is located in the engine compartment, between the end of the steering wheel coulomb and the steering wheel likage...Tom
You need an alignment.
Wheels are likely out of balance