Hi @Kemery7,
A warm welcome to the Bunnings Workshop community and thank you for your question.
Stainless steel typically has a brushed or grain finish. Working along the grain will give you the best results. In your example, you can see the grain along the bottom of the sink runs horizontally relative to the photo.
Start with a Scotch-Brite Non-Scratch Scourer Pads and rub the scratches gently along the grain. This may remove some of the finer scratches.
After this, use Rocket 0000 Super Fine Steel Wool in the same way as above to further remove scratches.
Then wet ultra-fine grit sandpaper like this 1200 Grit Wet And Dry Sandpaper and gently sand the scratched area following the grain.
After removing scratches, wash the sink out with clean water to remove any residue and buff the area with a soft cloth and 3M Stainless Steel Cleaner And Polish to restore shine.
Let me know what you think and if you have any further questions, please don't hesitate to ask.
Jacob
