Hairpins are symbols used to indicate gradual changes of volume in the score. There are two kinds: crescendo (getting louder) and decrescendo (getting quieter).
There are also crescendo and diminuendo lines which do the same thing:
All can be found in the Lines or Dynamics palettes.
To enter a hairpin from a palette use one of the following options:
To enter a hairpin using a keyboard shortcut:
To extend or contract the range of a hairpin, see Changing range of a line.
To change the height, select the height adjustment handle (shaded in the image below) …
… then use keyboard arrows, offsets (Properties panel), or dragging, to move the handle into the desired position. (See Basics: Adjusting elements directly.)
Alternatively you can adjust the "Height" in the Hairpin: Style section of the Properties panel.
To allow the hairpin to slope at a diagonal, check the "Allow diagonal" box in Hairpin: Style in the Properties panel. Then move the start/end adjustment handles to get the desired slope.
See Hairpin properties.
[To be added]
You can edit properties specific to hairpins in the Hairpins section of the Properties panel.
Niente circle: Places a small circle at the point of the hairpin.
Allow diagonal: Allows the hairpin to be set at an angle; see Changing appearance of hairpins (above).
Line style: Choose solid, dashed or dotted lines.
Thickness / Height:
Height (new system): Specify the height of subsequent hairpins if the first one spans a system.
Position: Above or Below.
Properties here allow you to specify beginning, end, and continuation texts and their vertical offsets.
Values of the "Style for Dynamics and Hairpin" can be edited in Format→Style→Dynamics & Hairpin.
Values of the "Style for text inside Hairpin" can be edited in Format→Style→Text styles→Hairpin
In Musescore 4.1.1, the "Style for Dynamics and Hairpin" : "Override score font" option does not affect haripin text, use "Style for text inside Hairpin" : "fontface".