The 24-year-old attacker took his tally to 15 for the season with two terrific strikes at Hampden Park, giving Rangers a deservedly emphatic win in their first game as champions
Templeton and Aird gave the visitors a 2-0 lead at half-time before Hemmings came off the bench to score his first goal for the club.
Templeton added his second and the Gers' fourth late on with a stunner from 25 yards before Lawrence Shankland headed a late consolation.
Ally McCoist made two changes to the side that drew 0-0, and subsequently sealed the title, in Montrose last weekend, as Aird and Anestis Argyriou replaced Hemmings and Chris Hegarty. Queen's Park boss Gardner Spiers, meanwhile, stuck with the same starting XI that drew 2-2 at home to Stirling Albion.
Aird, who scored the only goal the last time these sides met at Hampden Park, tested Neil Parry for the first time when he fired in a good effort from the edge of the box after a clever run and pass from Ian Black.
Templeton, enjoying a central role instead of his usual berth on the left wing, was always going to be a threat and he should have put the Gers ahead, running through the defence at great pace only to see his shot blocked by the onrushing Parry.
Jamie Longworth then headed wide from five yards out as the hosts hit back, losing Lee Wallace in the box to meet Andy Robertson’s left-wing cross.
Templeton, though, put Rangers ahead after 18 minutes, firing in from 20 yards out for his 14th goal of the season after a swift counterattacking move involving Wallace and Kyle Hutton.
Aird then won Rangers a free kick right on the edge of the box after his excellent run took him past a number of Queen’s players before he was pulled to the ground, but McCulloch fired the set piece wide.
Not to be denied for long, Aird scored Rangers’ second after 35 minutes with a close range tap-in, converting after McCulloch brought down a Black free kick and had a shot saved. The teenager's second goal of the season was his second at Hampden against the Spiders.
Ricky Little blasted a great free kick just wide from 21 yards out in response, a solid strike that had Neil Alexander at full stretch.
Blair Spittal and Robertson were a considerable threat on the left for Queen’s Park and they combined again, the former sending a ball across the face of goal with Aidan Connolly and Michael Keenan lurking, but neither could make contact.
Robertson’s long range shot was wide of Alexander’s goal as the Spiders started the second half just as brightly as their opponents.
Keenan played in a dangerous ball through the defence to Longworth but Sebastien Faure, in his natural position in central defence after a run in midfield, tackled excellently to stop Longworth’s advancing run.
Spittal then had a shot from the edge of the box deflected inches wide as the hosts ramped up the pressure on their opponents.
Substitute Hemmings, though, struck to make things certain for Rangers, smashing the ball in from inside the area following Templeton’s pass for his first senior goal for the club.
Templeton's second, and Rangers' fourth, was even better than his first, scooping a shot into the back of the net from 25 yards out.
The home side did have time to add a late consolation, however, when Shankland, a late substitute, headed into the back of the net for his 14th of the season.
Hemmings skimmed the post before going off with an injury before Tony Quinn struck the post for Queen's in the 93rd minute after a great Longworth pass. Templeton almost sealed his hat-trick with the last kick of the ball but Parry was equal to it.