Say good morning, or hello; ask how someone is doing even if they don't ask back. If you think something nice then say it, compliments are always a good idea. Don't forget to say thank you and you're welcome.
I love smiling at people and seeing them smile back, it's one of the most powerful forms of silent kindness you can perform
for yourself and others.
The power of an "I'm thinking of you" message whether it's received by text, card or handwritten note- it really is the thought that counts. So send it. It will mean so much.