In 1867 Craig was articled to the local Leith architect, James Simpson, to train as a draughtsman.
In 1871 he decided to train further as an architect and attended classes both at the Edinburgh Royal Institution and the Leith School of Art.
In the 1870s he worked as an assistant variously to Robert Rowand Anderson and John Lessels, before setting up his own practice around 1881.
[2] In 1885 he was styling himself “architect” without objection and running an office from 85 Constitution Street and living at 6 East Hermitage Place on Leith Links.
He is buried under a monument which he erected to his father, almost certainly to his own design, in Rosebank Cemetery in northern Edinburgh.