I tried to efile. It was rejected due to an error.I fixed the error and was told to print and file. I printed my taxes but there's nowhere to sign them. What do I do now

Look closely--the new "postcard size" Form 1040 is supposed to be two half pages--front and back--but when you print it out, both sides print on one page.  Do you see the black arrow pointing to the words "Sign here" in the middle of the page?

When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s.  Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS received the return.