The Modern Family star will present the show for the first time on April 7.
However, she told TV Guide that she has no idea what she'll be doing when she makes her appearance.
"Because I'm so new, I try to follow advice of the people who really know," she said. "So whatever... they believe I can do... I'll definitely do it."
One Direction will appear as the musical guests on Vergara's edition of Saturday Night Live.
The show airs on Saturdays at 11.30/10.30c on NBC.
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