Compliment people on their homes when you visit.
Write more than "Happy Birthday" in a birthday card. Think about the recipient and include a personal message.
If you open the free hotel toiletries but don't finish them, give them out to the homeless instead of throwing them away.
When you go somewhere to get or do something, ask the people around you if you can pick up anything they need.
If you have a bottle of perfume you don't like, leave it in a public bathroom for someone else to use.
After a wedding, donate the flowers to a nearby nursing home for residents or to a hospital for patients/nurses.