What do you wear on the beach when you go on holiday?
In English, we would be more likely to leave out the article :
I don't forget sunscreen, sunglasses and a swimming costume.
or use indefinite articles instead of definite ( a / some instead of the) :
I don't forget some sunscreen, some sunglasses and a swimming costume.
It sounds like you will be well prepared when you get to the beach! :-)