No one relishes the idea of composing a memorial card for a loved one who has passed. The bright side is that writing one of these is a way for you to gain some catharsis after suffering such a loss. It can be a little stressful, knowing that the deceased's family and friends will see the card, but so long as your heart is in the right place, the results will be more than satisfactory.
Assemble the pieces of information that go on most memorial cards. These include the name of the deceased (decide how he would want it written), the birth and death dates, and a recent photograph. Unless the deceased has specifically requested otherwise, don't use an old photo, as those at the funeral likely don't remember their loved one as a black-and-white World War II Army sergeant.
Find out the deceased's favorite books, sayings or passages of poetry. Not only could this give you ideas for what you should write, but a particularly meaningful quote could have a place on the memorial card.
Understand the restrictions of the memorial card form. First of all, you have only a very small amount of room in which to fit your message. This means, of course, that you must limit yourself. On the other hand, this can be a plus. After all, "brevity is the soul of wit," and restrictions can inspire you to be more poignant. You also have to present a favorable message that will not hurt anyone. Depending on the size of the font, you will probably have a limit of approximately 20 lines of up to eight words apiece.
Familiarize yourself with some classic tribute poems. A famous example is W.H. Auden's "Funeral Blues," which finds Auden's narrator so sad about his friend's death that the world should "stop all the clocks," as time has no meaning after the loss of his friend. Use this poem and others as inspiration for what you will write.
Allow the words to flow. Although you may be a bit emotional, it is best to simply get down whatever is in your head and heart. Funerals and other services are for the living, and so long as it comes from the heart, people will almost certainly like what you have to say.
Experiment with rhymed and unrhymed versions of your memorial card. Consider writing a brief account of a treasured memory you have of the dearly departed.