To make Custom Button in android follow the steps mentioned below:-

1) Create a drawable resource file in your drawable folder and name it custom_button.xml.

2) Add the code written below in your custom_button.xml file .

 custom_button.xml

<selector xmlns:android="http://schemas.android.com/apk/res/android" >
    <item android:state_pressed="true" >
        <shape android:shape="rectangle"  >
            <corners android:radius="90dip" />
            <stroke android:width="1dip" android:color="#5e7974" />
            <gradient android:angle="-90" android:startColor="#345953" android:endColor="#00ff55"  />
        </shape>
    </item>
    <item android:state_focused="true">
        <shape android:shape="rectangle"  >
            <corners android:radius="3dip" />
            <stroke android:width="1dip" android:color="#5e7974" />
            <solid android:color="#58857e"/>
        </shape>
    </item>
    <item >
        <shape android:shape="rectangle"  >
            <corners android:radius="90dip" />
            <stroke android:width="2dip" android:color="#5e7974" />
            <gradient android:angle="-90" android:startColor="#8dbab3" android:endColor="#00ff55" />
        </shape>
    </item>
</selector>

In the above code <stroke> tag is being used for outlining effect of the button and <gradint> tag is being used for shading effect in button.

3) Now call this file in the <button> tag's background property in your activity_main.xml.

activity_main.xml

<LinearLayout
        android:layout_marginTop="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginBottom="20dp"
        android:layout_marginRight="20dp"
        android:background="#ccffdd"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">
 <EditText
            android:id="@+id/email_et"
                android:layout_marginRight="20dp"
                android:layout_width="match_parent"
                android:hint="email"
            android:singleLine="true"
                android:layout_height="wrap_content" />
        <EditText
            android:singleLine="true"
            android:id="@+id/user_name_et"
            android:layout_marginTop="20dp"
                android:layout_marginRight="20dp"
                android:hint="User Name"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
        <EditText
            android:singleLine="true"
            android:id="@+id/dob_et"
            android:layout_marginTop="20dp"
            android:layout_marginRight="20dp"
            android:focusable="false"
            android:hint="Date of birth"
            android:inputType="date"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
        <EditText
            android:singleLine="true"
            android:id="@+id/mobile_no_et"
            android:layout_marginTop="20dp"
            android:layout_marginRight="20dp"
            android:hint="Phone Number"
            android:inputType="number"
            android:maxLength="10"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />


        <Button
            android:layout_marginTop="50dp"
            android:id="@+id/sign_up_btn"
            android:layout_width="150dp"
            android:layout_height="wrap_content"
            android:background="@drawable/custom_button"
            android:text="@string/sign_up"
            android:textSize="25dp"
            android:layout_gravity="center"/>
        </LinearLayout>