Edit brush strokes
You can edit any brush stroke in Microsoft Expression Design by selecting it from the Stroke Gallery (as though you were applying it to a path).
To edit a brush stroke
On the Properties panel, in the Appearance category, in the Stroke Gallery, select the brush stroke you want to modify.
On the Object menu, point to Stroke, and then click Edit Stroke Definition. Alternatively, you can click Edit Stroke in the Stoke Options pop-up menu in the Stroke Gallery.
You can edit a stroke using all the same techniques as you use when you create new custom brush strokes. After you edit a stroke, you can close the stroke definition window by clicking the close box in the flip tab or by clicking Close from the File menu. In the Save Stroke dialog box, Expression Design asks you to name the stroke and assign a category. If you don't change the stroke's name, the program asks you to confirm overwriting the original stroke file.