You find what you look for. If you look for the good things, you will see more of them... naturally... automatically... somehow the world becomes better without changing at all... And eventually you have to confront the fact that only you have changed... and it's probably for the better...

A lot of easy ways (1) tell the person(s) directly, followed by a firm handshake (2) a well thought-out letter of gratitude, (2) a small gift to make the person's work easier or more enjoyable, etc, etc.

Forgiveness frees us
Thankfulness enriches us
Kindness betters us all

Forgiveness frees us; Forgiveness is a gift you give yourself. When you hate something you chain yourself to it. When you choose to forgive those who have hurt you, you take away their power. Be quick to forgive, especially yourself. Let go or be dragged.

Thankfulness enriches us; Gratitude can turn a meal into a feast, a house into a home, a stranger into a friend. A grateful heart finds blessings like the magnet finds iron, cultivate it. We wait, starving for moments of high magic to inspire us, but life is full of common enchantment waiting for our alchemists eyes to notice. What consumes your mind controls your life. The words you speak become the house you live in. Your positive thoughts are both the prayer and the answer to your prayer. The moment you start acting like life is a blessing, it starts feeling like one. As you start to walk on the way, the way appears. It is not happy people who are thankful; It is thankful people who are happy. He is a wise man who does not grieve for the things which he has not, but rejoices for those which he has, Be content with what you have; rejoice in the way things are. When you realize there is nothing lacking, the whole world belongs to you.

Kindness betters us all; When selfish we neglect our fellow man. But when we think of others we better ourselves as well. Kindness has converted more sinners than zeal, eloquence, or learning. The miracle is this: the more we share the more we have. We rise by lifting others. The Ethic of Reciprocity aka The Golden Rule, Do unto others as you would have them do unto you. Kindness is in our power even when fondness is not. Everyone you meet is fighting a battle you know nothing about. Be kind. Always.

-various quotes

lately i’ve been replacing my “i’m sorry”s with “thank you”s, like instead of “sorry i’m late” i’ll say “thanks for waiting for me”, or instead of “sorry for being such a mess” i’ll say “thank you for loving me and caring about me unconditionally” and it’s not only shifted the way i think and feel about myself but also improved my relationships with others who now get to receive my gratitude instead of my negativity.

-Possible source Vijara

I always look at it as how would I like to have gratitude expressed to me.

I agree we should feel and express gratitude, but I'm terrible at it. I think it might help if I were to set aside 15 minutes each day to write down three positive things that happened during the day for which I'm grateful, but I've never penciled it into my schedule.

I make and give personalized gifts.

I try to tell all my friends they are important to me and that I appreciate them at least once every couple of weeks.

I’m a recovering alcoholic 4 years sober and gratitude is mandatory for long term recovery. It’s hard in the beginning but these days it’s second nature and it’s a MUCH better way to live.