This video explains how to create transcripts (same-language subtitles) for TEDx talks in the Open Translation Project.

To access the full transcribing guide, go to http://translations.ted.org/wiki/How_to_Tackle_a_Transcript

The TED Open Translation Project brings TEDTalks, TED-Ed lessons and TEDxTalks beyond the English-speaking world by offering subtitles, interactive transcripts and the ability for any talk to be translated by volunteers worldwide.
Learn more at http://www.ted.com/participate/translate