I've been thinking a lot lately about creating emotions in my writing, since I think that's one of the big reasons why we read. I love this quote from Becca Puglisi over at The Bookshelf Muse:
"...we hide our emotions all the time. And this means our characters should, too."
Becca Puglisi, Hiding Emotions: Just Act Normal, The Bookshelf Muse, May 8, 2013
This is so tricky to capture in a story.
I sometimes show my characters trying act normal (see Becca's discussion of the Just Act Normal technique) but with tiny physical cues that hint at their underlying emotional state. (Thank you, Emotion Thesaurus.)
In the past, I've left it at that and assumed the reader would somehow interpret what I was trying to do. But the more I learn, the more I realize how important it is to make it obvious to the reader what emotion the character is feeling and trying to hide.
This underlines again why it's so important to let the reader in on the character's thoughts and feelings (what literary agent Mary Kole describes as interiority). Of course, this is tricky too, because it has to be done a subtle, polished way to avoid the blatant "She felt..." or "He thought..."