How do you say Thank You?

I’ve been trying to get stuff together to send soldiers who have been injured and are at Walter Reed cards. I’ve almost got three per person. I’ve sent some and will send some more today. That’s not enough. But I don’t know what else to do.

Then today I took my car in to get the headlight changed. They did it and wouldn’t let me pay them anything. I told them you pay for expertise and I brought it in so they could fix it. They said they did and wouldn’t charge me for it.

How do I say thank you?