I will wear my heart upon my sleeve

Meaning

Display your feelings openly, for all to see.

Origin

From Shakespeare's Othello, 1604:

IAGO:
It is as sure as you are Roderigo,
Were I the Moor, I would not be Iago:
In following him, I follow but myself;
Heaven is my judge, not I for love and duty,
But seeming so, for my peculiar end:
For when my outward action doth demonstrate
The native act and figure of my heart
In compliment extern, 'tis not long after
But I will wear my heart upon my sleeve
For daws to peck at: I am not what I am.

See other phrases and sayings from Shakespeare.