Make them a big bag of confetti using a hole punch and colored construction paper. On each dot, write a quality of theirs that you admire: Generosity. Humor. Very Straight Nose. Never Stinks. Smiles at Dogs. If you need to write longer comments such as Always Shares French Fries or Can Be Trusted With Secrets, you can just cut out bigger circles (trace a quarter) and mix them in with others.
Pour confetti into a pillowcase. Show up at their house. Dump it on their head. Wait for a minute as they process what you are doing, which eventually will cycle from surprised...to annoyed...to grateful.