One of the simple things in a relationship that is overlooked as time goes on is simply holding hands. It was so easy when you were dating, you didn't even think twice about it. You didn't care who saw you holding hands, and it was a way of still touching the skin you so desired. Touch is a proven stimulant. This simple act can wake up nerves and get your blood pumping. Touch, simply put, is great for your relationship in general. I can speak from experience - when my wife puts her hand on my back or my arm when we are out and about I feel tingly where she touched me. The lighter the touch the more tingles I recieve. Sometimes the light touch however tickles. You might need to touch a little harder so as not to make it unbearable for the other person.
Do this next time your partner and you are out. Make it a point to hold his/her hand anytime you walk together. Not only is the touch good as mentioned above, but it also gets the two of you in sync as it makes you walk at the same speed and will usually slow you down so that you have more time to enjoy each other. Be a little silly with it. Maybe even try running while holding hands - just make sure to let go if need be. Dragging someone really messes up the momment. Get back to making it a natural function so that you just do it without even thinking. It might take some practice, but soon you won't be running your partner into things and you will learn to flow as a couple again.
For some more advanced hand holding you can try holding hands while snorkeling, skydiving, or for a real treat try making love while holding hands!