You can pause, smile, and start talking about something else, indicate that the moment is over by saying “Just thought you should know." You can even tell him you don't need to hear anything back, letting him know he should take some time to think things over. The less you come across like you're trying to extract a particular response from him the likelier he'll be to give you the one you want – if not immediately, eventually, when he realizes what a lucky guy he is. When talking, try to phrase everything personally -- "I realized I love you," "I fell for you, etc.-- instead of using language like "we" and "us." Because guys aren't always encouraged to communicate their thoughts and feelings, it's extra important to make them feel like they have someone to confide in. Be an active listener by reading between the lines, waiting for him to finish before you respond, and digging in with further questions. Avoid tying whatever he says back to yourself. You've told him you love him, now be patient as he works through his own emotions. Some silence, though it may feel awkward, is not a bad thing. He may be a bit shocked and need time to digest the news -- don't feel like one of you must always be talking. Just because you're not demanding a response doesn't mean you aren't pressuring him. If he disappears for a day or two, don't worry too much -- he just needs to process things. Chasing him down or following his every move, waiting to see how he responds, will only drive him farther away. If he is awkward or tells you he has other feelings, be kind and cordial -- you've done your part! But if he smiles or responds that he loves you too, there is no reason to rush down the aisle. Telling someone you love them in just another step in your relationship, not the end of the line. The important thing is treating him like you love him, not just saying the words.  Keep talking regularly, having open and honest conversations about your relationship. Don't feel the need to tell him you love him every day now -- actions speak louder than words. Ultimately, all you can do is express your feelings. You can't control how he is going to respond, nor should you. No matter what he says in return, you should respect his wishes and move on with your life. It takes a lot of bravery and passion to tell someone that you love them -- be proud of yourself for the effort and courage.
Make it clear that you don't demand to hear it back. Sit and listen to him after you've said your piece. Give him time and space to think. Continue treating him like a friend, no matter what his response, to help the relationship grow. Respect his decision or response without argument.