brushed finish

I have a 102 ''×102" piece of sheet metal 4 mill .stainless Steel.with a polished finish.i need to put a brushed finish on it #4.im using a stroke sander.all i need is something that i can blend it with.to take out the streaks. I have tried wd 40 . Windex. Water.any help would be great.if toy need more info let me no