Grass Skirt (Dollar Store) or Make Your Own
Hawaiian Lei Flowers (Dollar Store)
This one doesn't need a lengthy explanation, simple dress your child in a pair of shorts and attach a grass skirt (which are available at your local dollar store). You can attach lei flowers to the top of the skirt using hot glue. Create a bikini top by cutting an old t-shirt and attaching multiple flowers using a hot glue gun or the old fashioned way- with a needle and thread.
Adorn her hair with flowers.
I know I shouldn't have to specify this,
**Photo Credit - Submitted to Budget101.com by Jackie