Have a quiet workspace that is all yours to feel safe in. It could be a grove of trees outside your home, a special place in the house, or your own room. Hang beautiful fairy pictures all around to help inspire you.
One of the greatest story tellers of our time, Stephen King, says that if you don't have time to read, you don't have time to write. So read many books on the subject that you would like to write poetry about. In this case, poetry on fairies or fairy tales.
Beautiful fairies aren't the only fairies in the land. Use the famous question writers need to ask themselves; "what if?" and write about the fairies who don't make it into the ceramic collections on your mantle, the human sized darker fairies who love to trick humans and create mischief.
Write what you know. If you're out in the garden and there is dew on the morning flowers, write about it. Write in "normal" sentences and then break them down by taking out any unnecessary words. You will be left with the beginnings of a poem. For example;
"The morning sun shone on the dew in the flowers."
Now, take away all the "the's" and "on" (unnecessary words).
Now you have "morning sun shone, dew in flowers." Now separate the sentences and add imagination. What if a fairy popped up out of the flower, would she be watching you or just waking up?
Morning Sun Shone
Dew in Flowers
Fairy wipes her eyes
Yawns as I weed
Use analogies and compare yourself to the fairies. What would you wear, play, and eat if you were a fairy? Keep a notebook or, if you prefer, a journal handy so you can jot down ideas as they come.
Make the entire setting come alive. The fairy is yawning, but what of the flowers just opening up for the day, they seem to be yawning, too, don't they?
These are just suggestions. Keep trying, don't be too hard on yourself, and have fun. Your fairy poetry can be any length, it can rhyme or not, whatever you like.