<Button Content="I'm a Button; click me">
<Button.Template>
<ControlTemplate TargetType="Button">
<TextBlock Text="{TemplateBinding Content}" />
</ControlTemplate>
</Button.Template>
</Button>
https://stackoverflow.com/questions/7769979/wpf-button-no-border-no-background
И стрелочки до кучи
<Button FontFamily="Marlett" FontSize="20" Content="5"/> <Button FontFamily="Marlett" FontSize="20" Content="6"/>
