How can we show love to our teens?
Respect is an important aspect of love. Give your teens the same respect you expect them to give you. For example, you have every right to expect that they will not use profanity in your presence if you do not use profanity in their presence; or if you expect them to say "thank you" when you do something for them, try saying it when they do something for you (like taking out the garbage).
Saying "love you" at the end of a phone conversation is fine but try saying it after a serious disagreement or argument is resolved (even if they are not happy with the resolution). Don't get upset if your teen doesn't respond. They heard it.
A hug is wonderful but more important is a touch on the shoulder as you walk by them. If they ask why you touched them, the answer is, "No special reason, I just wanted to."
Don't become overly upset over minor things. Doing a chore an hour or two after you ask is never the end of the world.
Go to every game, play, concert - every everything your teen does. If you have to work and absolutely cannot go, make sure you remember to ask about it when you get home.
Let them see anger in your eyes when you are angry with them but never let them see hatred. Be sure you know the difference.