Add a up/down stroke
You can use the Up Stroke and the Down Stroke to indicate how a note/chord should be picked on fret instruments such as Guitars or Basses.
You will find the notation under the Tab toolbar. To use it, focus on a note then click on the stroke icon you want to add. Click again to remove it.
The stroke will be displayed on the TAB staff as an arrow indicating the direction the notes should be picked.