1. In a UIView subclass override Draw and set graphics context state.

var gctx = UIGraphics.GetCurrentContext ();
gctx.TranslateCTM (10, 0.5f * Bounds.Height);
gctx.ScaleCTM (1, -1);
gctx.RotateCTM ((float)Math.PI * 315 / 180);
gctx.SetFillColor (UIColor.Green.CGColor);

2. Create a Unicode text string.

string someText = "你好世界";

3. Create an NSAttributedString.

var attributedString = new NSAttributedString (someText,
       new CTStringAttributes{
	      ForegroundColorFromContext =  true,
	      Font = new CTFont ("Arial", 24)
});

4. Pass the NSAttributedString to a CTLine and draw the CTLine.

using (var textLine = new CTLine (attributedString)) {
       textLine.Draw (gctx);
}

You can draw text using the Core Text framework by creating an NSAttributedString instance; passing it to a CTLine instance and calling Draw on the CTLine. Otherwise, normal Core Graphics techniques such as obtaining a graphics context and manipulating the current transformation matrix apply. This example draws text of a given font and color and rotates it as shown above.