Yes you can go back into your return and fill out the estimated section. You aren't filling out a W4. You just search for that to get to the right place. You say No to W4 and it continues on to the Estimates. The estimates will be based on your estimated total for the whole year. They are just estimates. It will print out the 4 quarterly 1040ES slips. For the future ones you can adjust them either by going back into your return or just cross out the amount and write a new amount.
