diff --git a/how_to b/how_to
index a545947..a00f872 100644
--- a/how_to
+++ b/how_to
@@ -191,8 +191,13 @@ Suckless sent:
     Font:
         Hack
 
-Cut video/audio:
-    ffmpeg -ss "start" -t "duration" -i input.mp3 -acodec copy output.mp3
+Video and audio editing:
+    Cut video/audio:
+        ffmpeg -ss "start" [-t "duration"|-to "end"] -i input.mp3 -acodec copy output.mp3
+    Remove audio from video file
+        ffmpeg -i in.mp4 -an out.mp4
+    Nvidia hardware encoding
+        optirun ffmpeg -i in.mp4  -c:v h264_nvenc -crf 23 out.mp4
 
 RE .net apps:
     ilspymono <list-of-deps.txt>(can be empty) <exe or dll to disassemble> <output dir>