Help again please

You'll need a flat faced or planishing hammer and a steel block. This is the most basic of equipement, and won't break the bank and, if cared for, they will last a life time and more. It's important the that face of the hammer and hammering surface is smooth and free of pits and blemishes or they'll leave impressions on your metal.

I'm not sure how hammers are sold in the US. In Australia (where I bought all of mine), they are sold unfinished. I had to sand and polish them myself. Many flat hammers have a very sharp edge, I filed mine to a nice rounded edge. Then I start with a rough grit of wet and dry (such as 120) and work my way through the grits up to 2000. After that, wrap a piece of leather around a flat dowl, rub on some steel polish and polish the face of the hammer. I have also used jeweller's rouge quite succesfully to polish a hammer if steel polish was not available, provided the sanding back was very thorough.

This is a very good site for information:

Marisa (AUNZ) gave you excellent advice. If you want to try to do it cheaper (and less professionally), you could use a less perfect flat iron and cover it with leather (though you won't get as crisp a product) and hammer it with a plastic hammer. Or get a dappled effect by using a ballpeen hammer (round end).

But it's much better to get a proper hammer, dedicated to this purpose only.

Tina