Luggage and bags:
The weather is usually good during the summer, the sun is shining all day long and the nights are pleasant but a little humid. So bring light clothes, all your swimming gear, and a light jacket for the night. And if you think you are sensitive to humidity bring a warm one!!
There are super markets on the island where you can find almost everything you have forgotten to bring, though.
Plastic sandals for walking on the pebbly beaches will be useful.
Clothing/Shoes/Weather Gear: If you come in summer, don't expect much rain or cold days here. Bring a few T-Shirts, some short, beach sandals and a lot of sun lotion!