In the Paint Panel or Brush Options window set Wetness.

By default, most Marker brushes have a Wetness value of 0.5, which simulates ink from a somewhat used marker. You may want to increase the Wetness to simulate a brand new marker, or reduce the Wetness to simulate a dry or semi-dry marker.

When using a marker, pressing the stylus against the tablet without moving it will continue to apply paint to the canvas plane just like a real marker on paper.

If the Wetness is high (for example, 0.9), paint will be applied to the canvas plane more rapidly than if the Wetness is low (for example, 0.1). You can therefore create different types of strokes with a marker simply by moving the stylus faster or slower.