Using the Brush Tool, you can add styles to your lines. It can also be used to mimic calligraphy, crayon and brush strokes. This will help you add more life to your line works.
Select the Brush Tool and draw your object. Then go to your Brushes Palette and select the crayon brush to apply the effect.
To apply a calligraphy brush stroke, draw your path and select the calligraphy brush. Increase the Stroke to make it thicker.
To make changes to your calligraphy brush, you can double click the Calligraphy Brush to pop up the calligraphic brush options. Drag the brush to change the angle in the thumbnail. Change the Diameter makes it thicker.
Draw a rectangle and pick the border pattern. This will create a frame for it.
To crate a new brush. Draw a Star and drag it to the Brushes Palette. A New Brush selection appears. Choose New Pattern Brush for it.
Draw a circle and apply our new brush stroke.
Next draw a line path and apply the brush stroke. Double click the star brush from your brushes and set Scale and Spacing to 20% to get the effect below.
Brushes are very good for aligning objects and creating borders. So experiment with it and have fun!