Starting in 2004, Guðmundur was one of the founders of LTS Garðbær Studios (also known as LazyTown Entertainment), puppet performer and voice of Ziggy in "LazyTown". In 2010, he was a photographer for the Eurovision Song Contest. In 2011, he was the director and producer for the postcards of the Junior Eurovision Song Contest 2011 in the Armenian capital Yerevan.