Your pressure-sensitive pen tablet allows you to create smooth lines with a variety of widths and opacities that are virtually impossible to match using a standard mouse. Most graphics programs automatically detect your pressure-sensitive pen tablet, but some may require extra configuration. PaintTool SAI requires users of certain types of Wacom pen tablets to reset the pen tablet preferences so the pen works properly. You can reset your tablet preferences using the Tablet Preference File Utility that is installed with your Wacom pen tablet drivers.
Click the "Start" menu.
Click "Programs" or "All Programs."
Click "Wacom Tablet."
Click to open the Tablet Preference File Utility.
Click the "Remove All Preference Files" button to remove the Wacom tablet preference files.
Click the "OK" button and restart the PaintTool SAI program.
To activate the pressure sensitivity for the currently selected brush tool, click the "+" symbol next to the Advanced Settings text in the brush palette. Click to place a check in the Dens, Size and Blend boxes to activate pressure sensitivity.