新建窗体，并添加控件：PlotView，在load方法中添加如下代码

namespace OxyPlotWinform
{
    public partial class FrmStairStepSeries : Form
    {
        public FrmStairStepSeries()
        {
            InitializeComponent();
        }

        private void FrmStairStepSeries_Load(object sender, EventArgs e)
        {
            var model = new PlotModel()
            {
                Title = "StairStep"
            };

            for (int j = 0; j < 1; j++)
            {
                StairStepSeries sss = new StairStepSeries {Title = "Serie" + j};


                sss.Points.AddRange(new List<DataPoint>
                {
                    new DataPoint(0, 32),
                    new DataPoint(1, 23), new DataPoint(2, 54), new DataPoint(3, 32), new DataPoint(4, 65),
                    new DataPoint(5, 29), new DataPoint(6, 25), new DataPoint(7, 12), new DataPoint(8, 24),
                    new DataPoint(9, 32), new DataPoint(10, 25)
                });

                model.Series.Add(sss);
            }           

            plotView1.Model = model;
        }
    }
}

运行效果图：