What cultural faux pas should I try to avoid making in Cannes?

"It is important to be respectful of local customs when visiting a foreign country. In Cannes, remember to always use polite language when speaking to someone and to be mindful of when it is appropriate to speak. Never comment on someone's appearance or make negative remarks about another culture. Additionally, dress modestly when visiting religious sites, cover your shoulders and knees in public, and avoid kissing and hugging in public, as this can be considered too intimate. Pay attention to when it is customary to use a certain form of address, as this can vary from culture to culture. Finally, remember to be patient and kind when requesting help from local shop-keepers and other officials, as this will make for a friendlier interaction," said another expat in Cannes, France, France.