Baum started writing early in life, possibly prompted by his father buying him a cheap printing press. He had always been close to his younger brother Henry (Harry) Clay Baum, who helped in the production of The Rose Lawn Home Journal. The brothers published several issues of the journal, including advertisements from local businesses, which they gave to family and friends for free.[8] By the age of 17, Baum established a second amateur journal called The Stamp Collector, printed an 11-page pamphlet called Baum's Complete Stamp Dealers' Directory, and started a stamp dealership with friends.