Do's
Do give alms and make merit (or just witness the rituals if you are not a Buddhist)
Do use waterproof bags to protect your valuables
Do watch your belongings
Do use public transportation if you are heading to one of Songkran ‘hotspots’, as traffic will be paralysed
Do try wishing the locals a happy new year in Thai – “Sawasdee Pee Mai!”
Do smile and have fun