Want to add multiple contact for sharing information in windows phone 8.1 app developement

Hi all, I am very new in windows phone application development.
I am developing contact sharing app in which once a user clicks on Contact Push  radio button as mentioned below :

<StackPanel Margin="0,100,0,0" >
            <TextBlock Text="Mode of Sharing" FontSize="20" FontFamily="Segoe WP"  HorizontalAlignment="Center"></TextBlock>
            <RadioButton x:Name="SmsRadioBtn"  GroupName="MOS" Style="{StaticResource mosRadiobutton}" Margin="0,30,0,0">SMS</RadioButton>
            <RadioButton x:Name="BluetoothRadioBtn" GroupName="MOS" Style="{StaticResource mosRadiobutton}">Bluetooth</RadioButton>
            <RadioButton x:Name="EmailRadioBtn" GroupName="MOS"  Style="{StaticResource mosRadiobutton}">Email</RadioButton>
            <RadioButton x:Name="PushRadioBtn" GroupName="MOS" IsChecked="True" Style="{StaticResource mosRadiobutton}">Contact Push</RadioButton>
            <Button x:Name="sendContact_Btn"  Margin="20" HorizontalAlignment="Center" Content="Send" Height="65" Width="160" VerticalAlignment="Top" Click="sendContact_Btn_Click"  />
        </StackPanel>


A popup box should be open on click of contact push radio button  and in which I am able to add multiple number to whom I want to send the information.

Platform - WIndows phone 8.1
XAML and C#

Can you please someone help me how to create a popup layout having contact details information.