Disconnect the battery negative cable by loosening the 10 mm bolt and pulling the negative cable away from the battery post.
Before disconnecting the battery turn the steering wheel so that the front wheels are pointing straight ahead.
Wait 15 minutes before you start to work on the airbag system.
Push the airbag locking pins using a screwdriver. There are three pins that need to be pressed in order to release the airbag. Once the airbag is out, you need to disconnect the two airbag cables and the horn wire.
Loosen the 21 mm lock nut and remove the steering wheel. You will need to use a breaker bar to loosen the steering wheel locking nut. Rember to push the steering wheel on the opposite direction that you will be pushing the breaker bar. You don't want to put pressure on the steering wheel lock mechanism.
Mark the steering wheel shaft and the steering wheel. Also, make sure you don't spin the clockspring around. If you change the clockspring position, your stability or traction control may not work properly since it won't be reading the correct steering wheel angle.
Install the steering wheel in opposite order. Install the steering wheel to the steering column shaft.
To upgrade or replace the steering wheel on your Hyundai follow this tutorial. You will need to remove the airbag and the 21 mm locking nut on the steering column shaft. Mark the shaft and the steering wheel to install it in the exact same location. Otherwise, the steering wheel may be off center when you drive.
To replace the steering wheel buttons you will need to release and remove the airbag. There are a couple of screws that hold the steering wheel buttons in place. Remove those and pull out the steering wheel buttons. You don't need to remove the steering wheel itself.