public class XRDesignRibbonForm :
    RibbonForm,
    IDesignForm,
    IDisposable,
    ISupportLookAndFeel

Public Class XRDesignRibbonForm
    Inherits RibbonForm
    Implements IDesignForm,
               IDisposable,
               ISupportLookAndFeel

using DevExpress.XtraReports.UserDesigner;
// ...

private void Form1_Load(object sender, System.EventArgs e) {
    // Enables form skins in the application (if required).
    DevExpress.Skins.SkinManager.EnableFormSkins();
    DevExpress.LookAndFeel.LookAndFeelHelper.ForceDefaultLookAndFeelChanged();
}

private void button1_Click(object sender, System.EventArgs e) {
    // Create an End-User Report Designer form with a ribbon UI.
    XRDesignRibbonForm designForm = new XRDesignRibbonForm();

    // Create a new blank report.
    designForm.OpenReport(new XtraReport1());

    // Display the Report Designer form.
    //designForm.Show();

    // Display the Report Designer form, modally.
    designForm.ShowDialog();
}

Imports DevExpress.XtraReports.UserDesigner
' ...

Private Sub Form1_Load(ByVal sender As Object, _ 
ByVal e As System.EventArgs) Handles MyBase.Load
    ' Enables form skins in the application (if required).
    DevExpress.Skins.SkinManager.EnableFormSkins()
    DevExpress.LookAndFeel.LookAndFeelHelper.ForceDefaultLookAndFeelChanged()
End Sub

Private Sub button1_Click(ByVal sender As Object, _ 
ByVal e As System.EventArgs) Handles button1.Click
    ' Create an End-User Report Designer form with a ribbon UI.
    Dim DesignForm As New XRDesignRibbonForm()

    ' Create a new blank report.
    DesignForm.OpenReport(New XtraReport1())

    ' Show the Report Designer form.
    ' DesignForm.Show()

    ' Show the Report Designer form, modally.
    DesignForm.ShowDialog()
End Sub