Need GestureColor as transparent

I am implementing Gesture in my Activity in Android. Every time I am performing a Gesture, a yellow line is being drawn on the screen.

How would I set the GestureColor to transparent?

Try setting .setGestureVisible to false.

You might want to look at GestureOverlayView instead of just Gesture. With this class, you can easily put a color to the Gesture using setGestureColor. Check here for doc.