The Mermaidia dress pattern is a made to measure and size inclusive design, this means you measure yourself and then follow the instructions.
You will need any type of 4ply (fingering weight) cotton yarn in as many or little colours as you like, but if you are following the sample size, you will need 3 colours. You will also need a 3mm and a 3.5mm crochet, and some elastic (2-4mm) which will be joined into the top of the dress for extra hold.
The pattern is an advanced beginner level, however I have included very detailed steps and pictures throughout.