Poems/Blessings
The way that you release your doves should fit your personal style.  If you wish to have a poem, prayer, or blessing first, these are some popular options:

Irish Blessing
May the road rise to meet you,
May the wind be always at your back.
May the sun shine warm upon your face,
The rains fall soft upon your fields.
And until we meet again,
May God hold you in the palm of his hand.

May God be with you and bless you;
May you see your children's children.
May you be poor in misfortune,
Rich in blessings,
May you know nothing but happiness
From this day forward.

May the road rise to meet you
May the wind be always at your back
May the warm rays of sun fall upon your home
And may the hand of a friend always be near.

May green be the grass you walk on,
May blue be the skies above you,
May pure be the joys that surround you,
May true be the hearts that love you.

Blessing
Through the ages the white dove has been the symbol of peace, love, fidelity, and prosperity.  As a symbol of the joining of their lives (Bride and Groom names) will now release white doves.  The doves will fly up and circle above, and then fly home together as a pair.  (Bride and Groom names), we wish you a life of all the wonderful qualities represented by the white doves.  (Bride and Groom names), may your married life bring you many years of love, happiness, prosperity, fidelity, and peace.

Poem
Once the Lord of Heaven chose two doves,
Both young and fair,
And told them of a very special journey
they would share..

"Go now upon the earth and seek two hearts
Where you may dwell,
And there shall I surely come
And make my home with you as well.
We'll join the two and make them one,
A husband and his wife,
My spirit will endow their love
With everlasting life."

Today the doves still bring
The sacred promise from above
To those whose hearts are open
To the miracle of love.

                                    ~ Author Unknown