PFont font; // Declare the variable (do outside of setup, just like normal variables)

void setup()
{
  size(500,300);
  font = loadFont("Arial-Black-24.vlw"); // Load the font (do in setup as it does this over the network (sloooo)
        // Make sure you create the font first (Tools: Create Font)
}

void draw()
{
  background(0);
  textFont(font, 12); // Specify that the text you are going to draw should use that font and size
  text("My Name is Shawn", mouseX, mouseY);  // Draw the String "My Name is Shawn" at specific x and y coordinates
}