like this ...
VB Code:
  1. [color=blue]Dim[/color] img [color=blue]As[/color] Image = Image.FromFile("C:\tester.bmp")
  2.         [color=blue]Dim[/color] grp [color=blue]As[/color] Graphics = Graphics.FromImage(img)
  3.         [color=blue]With[/color] grp
  4.             .DrawString("some string of text", [color=blue]New[/color] Font("Tahoma", 10, FontStyle.Bold), [color=blue]New[/color] SolidBrush(Color.Blue), 20, 20)
  5.         [color=blue]End With[/color]
  6.         PictureBox1.Image = img
  7.         PictureBox1.Image.Save("C:\a_Bitmap.bmp")