StepLineExample.xaml

<UserControl x:Class="Wpf.CartesianChart.StepLine.StepLineExample"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:Wpf.CartesianChart.StepLine"
             xmlns:wpf="clr-namespace:LiveCharts.Wpf;assembly=LiveCharts.Wpf"
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300">
    <Grid>
        <wpf:CartesianChart>
            <wpf:CartesianChart.Series>
                <wpf:StepLineSeries Values="9,6,5,7,8,9,7,6,7,5"/>
                <wpf:StepLineSeries Values="1,4,3,1,4,2,1,2,3,5" AlternativeStroke="Transparent"
                                    PointGeometry="{x:Null}" StrokeThickness="3"/>
            </wpf:CartesianChart.Series>
        </wpf:CartesianChart>
    </Grid>
</UserControl>