A heartfelt thank you on paper shows how much you care.
As powerful for beginners as for veterans who have been branding themselves for years. This is so easy to do, it always amazes me that more people don't do it, or at least, don't do it enough. Thank people who deserve to be thanked, and even some who don't. Thank people who did something you appreciate, where it was done for you or someone else, regardless of whether they expected to be thanked for it or not. Thank people as soon as it occurs to you to do so, whether it was for something done 5 minutes ago or 5 years ago. They'll appreciate it either way.