Some stores that you might want to check out--
Forever 21 - I love this store there are a lot of options..a lot of cute short dresses..
Hollister - They have a lot of swimwear options, shorts , tank tops
J Crew - They are expensive but i really love their beach wear and dresses. Also check out their beach cover ups.
These are some of my picks for Hawaii for the non bikini bodies...
1. You can try a cinched skirt instead of a bikini if you have a broader hip or thunder thighs
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2. Floral short dress with slide sandals and a hat..
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3. Another floral dress from Hollister
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A few swimsuits, shorts, tank tops, short-sleeved shirts, sundresses, thongs, sandals and a hat and you are all set for Hawaii.