Besides showing love, your dog may be licking you for several reasons.
Your dog is happy to see you. It's their way to welcome you, like saying hello.
Your dog senses your emotions. If you seem unhappy, your dog may lick you.
Dogs connect with families via licking. Your dog licks you to groom and show affection.
Dogs can taste salt; they may lick you after eating or exercising. Your dog detects more subtle, attractive scents.
Dogs lick to get attention and affection, which reinforces the habit. They may also lick to ask for food.
Dogs that suffer from separation anxiety may get scared and lick whenever their owner comes home.