Last year for Halloween me and my friends decided to make a group costume, Mortal Kombat girls! We had a Jade, Mileena, and I was Kitana!  

We made all 3 of our costumes the same way, but in 3 different colors.  We bought 1 yard of stretchy fabric.  We all made our respective weapons.  Mine was a fan with 5 blades.  For Halloween purposes I kept it simple and cheap.  I bought flowing chinese dance fans from a chinese martial arts and imported goods store for about $3 and cut off the long ends.  I bought an aluminum pan from the dollar store and cut only 4 blades (I didn't do 5 because it didn't evenly match the number of wooden sticks on the fan).  I tried using a glue gun to attach it, but it did not work well, E6000 worked much better.  I then attached string and a clip at the end, so that I can clip it to my costume for easy carrying when going out.

For the boot covers, you can basically wear a pair of flats, and then wrap the fabric up and around your legs.  Pulling it tight as you can and pinning it from the foot to the thigh.  Cut off the excess fabric, and sew along the pins.  Unfortunately I don't have any pictures of the process, but here is an inside-out look of the boot covers on the right of the picture below.  Cosplay Island has a very good tutorial on how to make boot covers.  I also suggest sewing a piece of felt and/or gluing a layer of shoe rubber so the boot covers don't get as dirty on the bottom.

The rest of the costume consists of the mouth mask, arm bands and arm covers.  We bought matching shape wear and skin color tights to wear for the bottom part of the costume.

The mask is like a half circle oval shape, with the 2 sides taken in so it wraps around your face better.  2 elastic bands are sewn on to hook around the ears.