The Secret of Kells is a truly beautiful movie, and when I saw it, I wanted to make a costume of the faerie Aisling.
This is actually a pretty simple-and-quick-to-make costume (and fairly quick to put on, minus the body paint!)
So go watch the glorious animated movie, get inspired, and make a 'different' kind of fairy costume!

Step 1: Supplies

Dress and Legwarmers
Dress pattern - McCall's M6465
Flexible measuring tape
Pen
Pins
Scissors
Sewing Machine (or needle and thread if you're ambitious and don't mind spending time hand-sewing!)
Faux and/or Used Fur
Grey Fabric (for lining)
Elastic
Velcro
Old Shoes

Wig
Super extra long white wig (if you can't find a bangless one, you can just tuck and pin the bangs to the side)
Wig Cap
Hair Pins
Bobbi Pins

Makeup
Green Contacts
Alcohol-based airbrush paint
Airbrush
Buddy
Black eyeliner and mascara
White eyeliner
Powder
Razor
Soap
Rubbing Alcohol
Blush
Fake Eyebrows (or Black Eyebrow Pen; if so, you don't need the last two items)
Glue Stick
Spirit Gum

Step 2: Make the Dress and Leg Warmers

After I talked (well, more like tweeted one comment) to Tomm Moore, head guy for The Secret of Kells, I discovered Aisling's outfit was made of fur. Most people just do fur trim, but after finding out that little tidbit, well, I just HAD to go all the way.

First, using pattern M6465, I made a lining out of grey leftover linen, then ripped apart an old fur coat from ebay and began to make her dress using the same pattern. I simply tucked the lining into the dress and attached it, and the slip-on dress was done!

To make the leg-warmer boot-cover thingies, I measured the width of my calf, the length of my foot and from my calf to the floor. I added a few inches to each measurement, for ease and seam allowance. When you put all these measurements down on paper, center all your lines and then connect them, you'll get a trapezoid-shaped pattern. Cut out two fur leg warmers using this pattern. Fold down the top of the fabric/fur (wrong side to wrong side) about an inch or so, and sew it in place. Fold your leg warmer in half (good side to good side) and sew up the one side, leaving about a one inch gap at the top - so you can thread your elastic through the casing you had sewn earlier.

Cut a piece of elastic (at least) an inch smaller than your calf measurement, then thread it through the casing. Sew the elastic ends together, then the top of the leg warmer.

I wore shoes underneath my leg warmers, so I sewed a piece of velcro to the inside toe of the boot cover and to the toe of some old shoes, to help keep them in place.

In an alternate universe, Medieval-Raver-Kris would be proud

Step 3: Makeup-and-Hair Preparation

At this point, you may need to get your hair out of the way - both head-hair and body-hair! Alcohol-based airbrush inks are great in that they are long lasting and have strong colour, but they also cause all of the (microscopic) hairs on your body to stand up and stand out! So go shave; you might think you 'don't have hair' but hey, we're mammals, there is hair where you think there isn't, and it suddenly appears when you apply the makeup! If you don't care, more power to you. Otherwise, take a razor to your arms, neck, face, anywhere you will be applying the ink. (...don't shave off your eyebrows! Unless you do that already, then go nuts)

You'll be putting on false/drawing false eyebrows, so run a regular glue stick over your eyebrows (in the direction of hair growth) and pat down with powder. You'll finish these later.

You will definitely need to put your hair up for your wig. To help keep my wigs in place, I coil my hair up into small flat rolls and pin them to my head with bobby pins. I then put on a wig cap and secure it into place by pinning to to these rolls with hair pins. (There is a difference between bobby and hair pins!).

Step 4: Body Paint/Makeup

First, put in your contacts - if you're like me, hopefully now you can see, and you have the green-green eyes of Aisling.

After your skin is clean and dry, use the airbrush and your alcohol-based makeup to cover your skin. You may have to do a bit of practice to get an even coat. Cover your face, neck, arms and hands. It'll be a lot easier if you have a friend do this for you! Be very, very careful when using the airbrush over your face. Use a low setting!

Likely your lips won't take the ink too well - so I ended up going over my with white eyeliner and then powdering them.

Put on a bit of mascara, and a bit of eyeliner. You may have to use the white eyeliner in sections around your eye.

(When it comes time to remove the makeup, you'll have to use rubbing alcohol. Be careful!)

Step 5: Put on Tights, Dress, Leg Warmers and Eyebrows

Put on your white tights (saves you from having to paint your legs!), your dress, leg-warmers (and shoes) and your eyebrows!...

...if you bought false eyebrows, put a bit of spirit gum (or other skin-safe-adhesive of choice) on the back of them and stick them over your real (already glued-down, powdered and now alcohol-inked) eyebrows. If you're drawing them on, use black eyeliner (or black makeup) to draw on big, bushy eyebrows.

(I know, I know. Scary pic - it was for a makeup test)

Step 6: Wig - and You're Done!

Now all that's left is the wig. Normally I flip the wig upside down and put it far down on my forehead, then bring it back down to the base of the skull and adjust the front once it's on. Since this is a super super super long wig, I really just 'set' it onto the top of my head, then maneuvered the sides around until it looked and felt snug. I then used (silver) hair pins to hold it in place.

And you're done! Go run and frolic in the woods and turn into a wolf if you can!