Ryan and his fellow board members have drawn up a shortlist of candidates to replace Brian Flynn and the interview process will begin this week.
"It has served us well in the past, and it's time to put that selection 'matrix' of ours to good use again," wrote Ryan in his column in the Doncaster Free Press.
"Applications are currently coming in and this last week has seen the club linked with the likes of Paul Dickov, Terry Butcher, Neil Warnock and, following his dismissal from Wolves, our former manager Dean Saunders.
"Rest assured we will be looking to continue the success we have had with managers since we appointed Dave Penney and Sean O'Driscoll.
"Terry Bramall, Dick Watson and myself have discussed the criteria at length and we came up with 18 salient points that will eventually decide the man for us.
"A handful of these include: good at buying and selling, good communicator, good contacts in the game and works well in the community. But above all he will be a proven professional, possess his coaching badges and have a proven track record."
Doncaster are looking for a successor to Flynn, who guided Rovers to the npower League One title this season after taking over from Saunders in January following his departure to Molineux.
Flynn was handed the reins on a caretaker basis before being given a contract until the end of the campaign and the former scout will now revert back to that role under the new manager.