Q. How can I indicate a spelling mistake in a quotation in APA Style?

APA 6th Edition

If “incorrect spelling, grammar, or punctuation in the source might confuse readers, insert the word sic, italicized and bracketed, immediately after the error in the quotation” (American Psychological Association, 2010, p. 172). For example, “they made they're [sic] lunches." 

Reference

American Psychological Association. (2010). Publication manual of the American Psychological Association (6th ed.). Washington, DC: Author. 

APA 7th Edition

If “incorrect spelling, grammar, or punctuation in the source might confuse readers, insert the word ‘[sic]’, italicized and bracketed, immediately after the error in the quotation” (American Psychological Association, 2020, p.274). For example, “they made they're [sic] lunches.” 

Reference

American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.). https://doi.org.10.1037/0000165-000