Begin with brief gentle touches in places your dog already tolerates. Don't overwhelm them.
Give treats as you touch so they associate physical affection with positive things.
If they move away or seem uncomfortable, give them space. Don't force interaction.
Verbally praise and gently pet your dog when they remain relaxed during touch.
Teach them to touch their nose to your hand so they learn to approach touch voluntarily.
Make brushing, nail trims, and handling part of routine with treats so they accept it.
The more positive physical affection you give your dog, the more comfortable they'll be.