Prepare the countertop. Spray the counter with a degreasing cleaner. The entire surface needs to be clean and dry.
Cut the stainless steel sheet to fit. Measure out the countertop. Use metal nippers to trim the sheet to fit. Work slowly -- it is better to trim off excess than to get stuck with an unusable and too small sheet.
Apply adhesive to the counter. Make a zig-zag pattern on the counter with the adhesive.
Apply adhesive to the stainless steel sheet. Flip the sheet over and use the same zig-zag pattern on the back when you are applying the adhesive.
Place the sheet on the counter. Start in one corner. Line it up and lay the sheet down. Make any necessary adjustments quickly, before the adhesive sets. Press the sheet down firmly. You can also hold it into place with padded vise clamps to get a good seal.
Trim off the counter. Bend stainless steel counter trim along the edge of the counter. Insert screws through the trim to fasten it to the edge. Trim it to fit with metal nippers.