Practice Being Happy
What we practice, we become good at. It's that simple. Most of us practice our bad memories, our grievances and resentments. Take the time to really enjoy each moment that you can. Notice everything about it, and pack your memory with as much detail as possible.
By changing our thinking and creating happy, empowering thoughts, we have a recipe for flying high and letting our imagination take us to amazing places. Choose the good gifts in life to open again and again. The "old-fashioned" idea of counting your blessings turns out to be good for your body in addition to your peace of mind. 
Creating Your Happy Journal
Find a beautiful book and start entering memories,thoughts, comments, pictures... anything that makes you feel good. Add gratitude and goals, hopes and dreams and you've got a powerhouse in your hands. Make it real for you.
Learning to practice being happy works hand 
in hand with releasing bad memories. Both sides of the coin are necessary for success. The best happy memories are ones that you use often!
Feeling Good! 
Set up a scrapbook or Pinterest page with pictures that make you happy
Just by chance, after I had created some Pinterest pages, I noticed that my "Been There... Seen It" page  — about all the places I had been — made me feel really good. And I liked re-visiting it again and again. Find things that do that for you! 
Here is a link to my Pinterest page.
Sing, dance, look at something beautiful! Practice changing your emotional state to feeling good!
Create a playlist with content that makes you happy
Look for music and/or videos that make you feel good and have hopeful, positive content. The kind that mellows you out or make you want to take on the world. Get singing! And tap out any bad, sad or mad references to old favorites to reclaim them!