This is the Beach Goddess Maxi that Rae from Made By Rae created from some gorgeous cotton rayon challis. It’s super easy to make, using elastic thread shirring to create the stretchy strapless bodice. (Straps are an easy addition, if you feel more comfortable in a dress with straps.) A long gathered dress like this is best made from a lightweight, drapey fabric like a rayon challis or perhaps a jersey knit. Go to Made By Rae for the tutorial.
[photo from Made By Rae]