Returning to Australia, Wilton became General Staff Officer Grade 1 in Major General Stanley Savige's 3rd Division in August 1942. Savige later recalled that "I never had a more competent staff, nor such a co-operative team, than that staff after Wilton came along." The 3rd Division was part of Lieutenant General Edmund Herring's II Corps. In October, Herring succeeded Lieutenant General Sydney Rowell as commander of New Guinea Force, and Savige became acting corps commander. With his attention focused on the corps, Savige relied on Wilton to supervise the training of the 3rd Division. Wilton travelled to New Guinea in February 1943 to reconnoitre the terrain and begin plans for the division's forthcoming campaign in Salamaua. He was attached to Kanga Force in Wau during March 1943, prior to its absorption by 3rd Division the following month. Herring had ordered that the 3rd Division "threaten" Salamaua, and despite Wilton's attempts to clarify precisely what this meant, the order remained vague. Savige and Wilton interpreted it as meaning that the 3rd Division was to capture Salamaua, when in fact its main purpose in the campaign was to divert Japanese forces from Lae. In any event, 3rd Division progressed steadily and by August it had to be ordered to slow down so that Lae could be attacked before Salamaua. Wilton received much of the credit for 3rd Division's performance. He was awarded the Distinguished Service Order (DSO) for his "skill and ability in New Guinea" between July 1942 and April 1943, the citation being promulgated on 27 April 1944.