Whoa! Aluminum is harder than silver, and will scratch unless you are very careful. (Ask me how I know!) The foil tarnish removal step is a good one, but follow it up with traditional silver polish.
The point of the electrolysis process with the foil and salt solution is NOT to remove silver. Silver polishes remove silver, and it is only very very thin. A jeweller friend suggested the blue silver polishing cloths are the best way to get the desired finish after the foil trick, and these blue cloths leave a protective coating too.