Mistep or Misstep: How To spell?
The word Mistep is misspelled against Misstep, a noun meaning "A wrong step; an error of conduct."
Misstep has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings mi & tep which should not be misspelled with single 'S'
Wrong Spelling:  mi-s-tep  Correct Spelling:  mi-ss-tep 
Find more wrongly spelled words of Misstep to spell it well.