Yes and no. GDPR requires from all organisations collecting personal data to apply ‘data minimisation’ and to have a legitimate reason to store any sort of information about clients. You are only allowed to store data that you need to do your job or that is in the client’s own interest. So, noting what colour you use for the treatment is information you need. Noting when they’re going on holidays, could be information you need in the context of booking a new appointment, for example. Detailed family status might not fall into ‘legitimate interest’ although you might put the client in a marketing category for ‘Mothers’ for example – that is, if they agree to receive marketing offers, updates and promotions.
– If you are not a Phorest Salon Software client and work with pen & paper, please note that all these little notes you might stick into your appointment book or the client’s record is part of the data you have to carefully store and keep a trail of (i.e. it does not matter if data is in the computer system or on paper, it’s all personal data).