He worked as a truck driver for a local factory and took voice lessons just for fun; in 1950, he even entered the Stockholm Opera Academy, but soon backed out since he didn't like it, and studied operetta instead, while singing in a male quartet. His stage debut came at the Royal Opera Stockholm in 1955, as Orphée in Offenbach's operetta; he was successful, and became a permanent member of that theater, and stayed until 1981.
Although he sang leading roles sometimes (Duca, Hoffmann), his realm were the comprimario parts: Bardolfo, Triquet, Missail, Hauptmann in Wozzeck, David. He sang a lot of Swedish opera, also several world premieres. Vikstöm was popular on the Swedish radio, where he sang light music, and appeared in eleven films and on TV, also after his stage career was over.
When this recording was first posted on Historical Tenors, the tenor was thought to be Kolbjørn Høiseth. Then Stefan Johansson (head dramaturg Malmö Opera, 1997–2014 of the Royal Swedish Opera, Stockholm) provided the following correction.