Ease them in one garment at a time. Start with a Classic Sleeveless Tee, move up to a Long Sleeve Tee once they're comfortable, and then see whether they'll entertain Long Johns.
Your new hound may never have worn a coat, so clothes can be a whole new idea. Before you dress them for the first time, gently play with their paws so they get used to having their legs handled, because you'll need to lift their front legs. Treatos, scritches and lots of praise help.
Every hound is different: some bound around the house in their first tee, and others do a statue freeze. Not every hound likes back legs either, and a long sleeve tee or a Snuggle Sweater keeps those hounds warm without them.
Our step-by-step dressing guide covers getting legs in and out, and the clothing guide has a video from Auntee Jen.