Step 1: Choose the right shampoo
Many brands have an after-sun shampoo on the market nowadays. One of our favorites is the Color Extend Sun one from Redken. It easily gets rid of traces of chlorine, salt and whatever ends up in your hair after a long day of relaxing on holiday. Tested and approved.
Also an option is buying a good intense repair shampoo before leaving on vacation. We often use the Susanne Kaufmann one when reaching another hair crisis. Works perfectly all year long.