Hello and welcome! I am Kyle and will guide you through this tutorial on how to add subtitles to an existing video using AEGISUB, a free, cross-platform open source tool for creating and modifying subtitles. First, you must have the VIDEO and the EXACT SCRIPT available in a local folder. It is important to foresee a DIFFERENT FOLDER for EACH video because the standard requires that the filename of subtitles is always the same. Open the script and have it ready for later. Open AEGISUB and IMPORT the video by clicking on "Video", followed by "Open Video" and then by finding the video in the right folder. To import the audio from the video, click on "Audio" and select "Open Audio from Video". You are now ready to add the subititles to the video. This can be done by following these steps: 1. Listen to the audio and select an appropriate time period to add subtitles, for example, a full sentence. A time period should not be too long or too short, so that the subtitles roll smoothly on the screen as the video frames change. 2. Position the pointer at the beginning of the time period, by playing it and pausing at the moment the speaker begins to talk. 3. Mark the beginning of the time period by right-clicking on the space below the video and selecting "Insert at video time (after)". 4. Find the point at which you wish to stop the time period, indeed when the speaker has finished a sentence or during a moment of silence. 5. WRITE DOWN the time value of the moment you stopped into the END TIME box under the audion graph. You can see it from the "Current frame time" value under your video. To check that this is a suitable time period, click on "Play current line". You will only hear the audio from the time period you have selected. 6. Copy and paste from the script the correct subtitles for the time period. Repeat these steps throughout the rest of the video. Once you have added all the subtitles to the video, SAVE the subtitles' file AS Video-subtitles.ass and EXPORT it into a '.srt' file. Go to your folder, right click on the '.srt' file, click on "Open with.." and open the file with your prefered editor. Copy the file content and paste it in the web page 'webvtt.org'. Your '.srt' file has now been converted into a '.vtt' file, which is the STANDARD format and filename for subtitles. '.vtt' files differ to '.srt' in that their timecode fractional values are separated by a full stop instead of a comma. Copy and paste the content of the just-created .vtt into your editor. Click "Save as...", then make sure the 'Save as type:' is changed to 'All files'. Save the '.vtt' file as 'subtitles_en.vtt', if the language is english. You can see on THIS page https://support.orbweb.me/hc/en-us/articles/204007850-File-naming-convention-to-show-subtitles-with-video-files the standard filenames for other languages. Good job! You made your first video with subtitles and subsequently converted it into a standard '.vtt' file. Thank you very much for following this tutorial!