You just need to style your LinePageIndicator in your .xml layout file.
EX:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<android.support.v4.view.ViewPager
android:id="@+id/pager"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
/>
<com.viewpagerindicator.LinePageIndicator
android:id="@+id/indicator"
android:padding="5dip"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
app:strokeWidth="4dp"
app:lineWidth="30dp"
app:unselectedColor="#FF888888"
app:selectedColor="#FF880000"
/>
</LinearLayout>