How do I pay my estimated taxes for 2018 using TurboTax?

[DoninGA]

You would have to print and mail the Form 1040-ES with your payment to the IRS.

See this TurboTax support FAQ - https://ttlc.intuit.com/questions/1900683-how-do-i-print-estimated-tax-vouchers-for-my-2018-taxes

Or use the IRS website for payments - https://www.irs.gov/payments