Get customer details out of your phone into one simple list

Help me set up one simple customer list.

My business: [what you do]
Where customer details are now: [e.g. phone contacts, WhatsApp, email, notebook]
What I'd use the list for: [e.g. reminders, offers, repeat bookings]
Tools I already use: [e.g. Google Sheets, Excel, invoicing software]
Roughly how many customers: [number]

Ask me up to 3 short questions first. Wait for my answers.

Then:
1. A list layout with columns, kept short.
2. A 5-minute weekly routine to keep it up.
3. A plan to gather old details over the next month.
4. A note on keeping details safe and only using them as customers would expect, with a pointer to the ICO's guidance for small businesses.

Simple, UK English.

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