Whether you want an easy homemade costume because you can't sew or you just don't have a lot of time, pirate costumes are not hard to pull off. Costume creation is all about giving the impression of a character, not a replication of a character's look. In some cases, replication of a historical character's look and dress hinders recognition of a costume because people have an image in their minds that may differ from reality. Pirate costumes are easy to recognise because many people have the same ideas as to what a pirate looks like.
Pirate costumes are all about the accessories, but the clothing base that the accessories are put over is also important. Girls have more options than boys do since they can wear a skirt or trousers, depending on their preference. For the shirt, a large white or tan coloured shirt will do the trick--the more voluminous the sleeves, the better. (Buy it oversized.) Blouses work well for a pirate top. Pair the shirt with a vest. If you want to wear a skirt, go for a full one in a dark colour, to the knees or longer. From there, either pin up the skirt with safety pins or cut a large zigzag pattern at the hem of the dress and let it fray. If you'd rather have trousers, choose a wide pair. Add zigzag cuts, tucking them into wide boots or leaving them hanging.
Accessories really make the pirate costume. Tie a red sash around your waist, leaving long, hanging ends. The sash can either be a scarf or can be cut from a slightly stretchy red fabric. Tuck a cutlass into the belt, either a plastic one from a costume shop or one cut from cardboard. Wrap the blade portion in aluminium foil or duct tape and wrap the hilt with black electrical tape. Use a solid colour bandanna or more material from the sash to make a head wrap. Making a pirate hat goes outside the realm of easy, so buy a pirate hat from a costume shop or glue a skull and cross bones on a wide-brimmed black hat. Wear large gold hoops for earrings and add a jaunty eye patch over one eye. Pirates are always after treasure, so tuck a few "gold" bead necklaces into the sash or tie on a drawstring pouch and have the beads dangle from that.
Make-up is the finishing touch for an easy pirate costume. Use bronzer on your face and any other exposed skin to create a tan since pirates spend so much time in the sun. Eyeliner for older girls can help transform their face to create a fierce-looking pirate. Brown or mauve lipstick also helps darken the look. Pirates are often dirty, so apply more bronzer or smudge black eyeliner in places.