 After the completion of his recruit training at Hrozpur, Mohan Singh was posted to the 2nd Battalion of the Regiment, then serving in the North-West Frontier Province.He was selected as a potential officer in 1931, and after six months' training in Kitchener College, Nowgong (Madhya Pradesh), and another two and a half years in the Indian Military Academy, Dehra Dun, he received his commission 1 February 1935 and was posted for a year to a British Army unit, the 2nd battalion Border Regiment.He was them posted to 1st Battalion, 14th Punjab Regiment on 24 February 1936, which at that time happened to be stationed at Jhelum.