Diy Corrugated Metal Retaining Wall . Steps 1 measure and mark for your feature wall. We earn a commission if you make a purchase, at no additional cost. Corten corrugated steel Corten, Corten steel, Rustic house from www.pinterest.com The cheapest way to build a retaining wall is to diy it. Showing my design of a galvanized steel raised bed that also acts as a retaining wall. Diy steel retaining wall advice.