Create a custom Style and use it for Button with Style element and Setter element
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"> <Page.Resources> <Style x:Key="MyStyle"> <Setter Property="Control.Background" Value="Red" /> <Setter Property="Control.Foreground" Value="White" /> <Setter Property="Control.Width" Value="100" /> </Style> </Page.Resources> <StackPanel> <Button Style="{StaticResource MyStyle}" Content="Button"/> </StackPanel> </Page>