A simple example for setting styles in silverlight.
In silverlight we create styles in app.xaml
<Application.Resources>
<Style x:Key="TitleBorder" TargetType="Border">
<Setter Property="CornerRadius" Value="10"/>
<Setter Property="Background" Value="#FFDEDEDE"/>
<Setter Property="Margin" Value="0,0,5,0"/>
</Style>
</Application.Resources>
In xaml where you want to apply the style,
<Border Style="{StaticResource TitleBorder}">
<TextBlock Text="SEARCH"/>
</Border>