This is a video on the procedure involved in changing out your seat belt webbing to a colored version. This vehicle is a 2017 Sonata SE but the process of removing the webbing is the same regardless of the vehicle unless you have a specialty or higher end car in which case your vehicle may start to involve electric motors and such on the belts.

Disclaimer:
WARNING! Do not attempt to sew or assemble seat belts unless you are a qualified manufacturer. Manufacturing seat belts requires very specialized thread, sewing machines, assembly skills & knowledge of federal Standards. If you do not possess all the equipment, skills & training necessary to manufacture a seat belt, please do not attempt to: repair, re-web, restore, upgrade, alter or build one yourself. Failure to follow this warning could result in serious injury or death in the event of a crash. By attempting anything you see or will see in this video, you are (1) accepting sole responsibility for any physical, emotional, mental, or bodily harm that may or may not occur to you, your passenger(s), or the occupant(s) of any other vehicle that you may or may not make contact with on or off the road. (2) you are here by relinquishing me of any and all liability or legal action(s)...

Professional installers:

https://www.seatbeltplanet.com/

https://www.safetyrestore.com/

Belt webbing used:

https://www.ebay.com/itm/Seat-Belt-We...

#69 Thread Used:

https://www.amazon.com/dp/B01G4ATJIS/...

Needles Used:

https://www.amazon.com/Singer-75467-S...

If you have any questions do feel free to ask and I hope you enjoy the video.