The Open History Project aims to preserve history the way people experienced it.
The way people speak often reflects the way they experienced situations. We therefore try to keep individual speech patterns; on the other hand, we want readers to be able to read texts with ease. It is upon you to find the middle way.
The general idea though is to edit as little as possible.
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False Starts: False starts can be anything from single words to a sentence fragment. They may reflect the speaker’s emotions, thoughts and mood. It is upon you to decide whether it is justified to keep or delete them.
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Repetitions: As with false starts, they might be of importance to reflect the speaker’s experience; you will need to decide whether to keep them or not.
They should be kept when they are used to put emphasis on something.
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Feedback Sounds: Interviewers often give feedback sounds like “Yes,”
“Aha…” to encourage the speaker to continue. Only when these sounds are a direct form of feedback to a previously made statement should they be kept.
 Grammatical Mistakes: People make grammatical mistakes when they speak.
Even native speakers of a language do this. For native speakers, their grammatical mistakes often reflect their stream of thoughts and emotions or their background. Therefore please don’t correct mistakes. When the interview is not conducted in the speaker’s native language, you may choose to correct grammatical mistakes. Just consider how will affect the text. If you do an interview with an immigrant about learning your language, it might not be in your favor to correct mistakes.
 “Strange” Choice of Words: As for the latter points, the choice of words may reflect the speakers thoughts and experiences. If the speaker is not a native speaker of the language the interview is conducted in, his or her choice of words can tell us a lot about his or her native language, about sayings and connotation. If that is so, it makes sense not to change it.
When you edit a transcript you need to make clear, which parts you edited. We cannot claim that an interviewee said certain things if he didn’t or didn’t say it the way the edited version of the interview reports his speech.
Therefore always use these brackets [] to mark changes.

When leaving out something, put the brackets with three dots in place:
“I would like to tell you about – wait, what was her name again? Lisa? Laura? Ah yes,
Lauren! Lauren.”
Could become…
“I would like to tell you about […] Lauren.”
“We went there in the afternoon.”
If it is not clear what “there” refers to, this could become…
“We went [to the police station] in the afternoon.”