Open the lead and convert it. It becomes a customer record carrying the name, contact details and anything else you captured, so nothing is retyped.
When to convert
When they book, buy or otherwise become real. Converting too early fills your customer list with people who never came back and converting too late means typing their details in twice.
What comes across
The contact details you hold and the notes you have added. The lead history stays attached, so you can still see where they came from.
Straight to a quote
A lead that needs a price does not have to be converted first. Raise the quote and the customer record is created as you go.
Marketing consent
Converting a lead does not create consent to market to them. Somebody enquiring about a haircut has not agreed to a monthly newsletter. Consent is recorded separately and deliberately.
Common questions
Does converting delete the lead?
No. The lead is marked converted and stays in your history, so your pipeline reporting still adds up.
What if they are already a customer?
Existing customers are matched on email and phone, so you get a note against the customer you already have rather than a duplicate.
Can I convert several leads at once?
Convert them one at a time. It is a deliberate action and in practice you want to check the details as each one goes across.