Once you prepare the estimates as above, as for payment options you could print out the quarterly 1040-ES vouchers and pay by check in the mail.
Or if you don't want any paperwork to mess with and don't want to pay by check, you have a couple of free electronic options.
You can pay each quarter at the IRS.gov website for free using direct debit from your bank account, and can print out a confirmation. There is no fee for an ACH electronic payment from your bank account. There IS a fee if you use debit card or credit card, however.
<a rel="nofollow" target="_blank" href="
https://www.irs.gov/payments/direct-pay">https://www.irs.gov/payments/direct-pay</a>
If paying there, be sure to print out the confirmation page for your records.
It's quickly becoming too late to use the next method for this first quarter's payment, since you may not have time to get it set up before April 15. But if you will be making estimated payments for some time to come, you may want to consider setting up a free payment account at the Treasury's EFTPS website. The Treasury has a site called EFTPS.gov where many types of tax payments can be made, including quarterly estimated taxes or even tax due from a Form 1040, etc. You have to open an account and get a PIN (which they send in postal mail). You can also use the PIN to make telephone payments from your bank account. We can tell you more about EFTPS.gov, but time is running short to get that set up before April 15 since it takes a few days to mail the PIN.