"I think we had to talk about the fact that he wasn't there," Priestley told ET Canada.
"And I think we've done it in a tasteful way that's not exploitative. You know it's a difficult line to walk.
"It's not like you really know how to do it because it's not something you do every day.
"So hopefully we've done it in a way and we've been successful in navigating those waters successfully."
Priestley also admitted that it has been "good" for the cast to be together following their former co-star's death.
"I think that all of us being together has been good," he said. "Obviously, Luke not being there ... Luke was a big part of that cast and a big part of our family and his absence is definitely palpable but I think all of us being together has been good for all of us."
Meanwhile, the upcoming fourth season of Riverdale will be dedicated to Perry, and will be the show's "most important episode ever".
Showrunner Roberto Aguirre-Sacasa took to Twitter last month to share a picture of the script for the episode - which is titled In Memoriam - and the screenwriter admitted he was "thankful for the opportunity" to pay tribute to the late actor and his character Fred.
Aguirre-Sacasa said at the time: "Probably the most important episode of #Riverdale we'll do this year, if not ever. A tribute to our fallen friend. Thankful for this opportunity to honor Luke & Fred. (sic)"
Aguirre-Sacasa has written the episode, which will be directed by Gabriel Correa.
Perry was last seen on the teen drama series in April, a month after he passed away, but the fate of his alter-ego Fred is yet to have been addressed on screen.
