Let the sun reflect your clothes like the woman in this picture by The Sartorialist or bright up your white tee with a plastic pearl necklace like this from Cubus.
This girl from Oslostil wears her yellow perfectly.
The tube dress is available at H&M looks summer bright and will fit just as well at the beach as in the city, depending on how it's styled.
As bright colours come and go in the world of fashion, I would opt for the less expensive high street stores when shopping for yellow. This is a typical summer trend, so there's no need to splurge out on the most exlusive designer wear. H&M, Zara, and Gina Tricot all have plenty of styles that don't ruin your holiday budget:)