Help with a picturebox.

[Ellitivity]

OK. So I'm making a simple game that is a car that moves around the screen according to the arrow keys. i have made code to rotate the car inside the picturebox, but i don't know how to make the car move in the direction that it is facing after the turn. please help. my code so far.....

Imports System.Math

Public Class Form2
    Private Sub tmrRotate_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles tmrRotate.Tick
        Dim bm_in As New Bitmap(picCar.Image)
        Dim wid As Single = bm_in.Width
        Dim hgt As Single = bm_in.Height
        Dim corners As Point() = { _
            New Point(0, 0), _
            New Point(wid, 0), _
            New Point(0, hgt), _
            New Point(wid, hgt)}
        Dim cx As Single = wid / 2
        Dim cy As Single = hgt / 2
        Dim i As Long
        For i = 0 To 3
            corners(i).X -= cx
            corners(i).Y -= cy
        Next i

        Dim theta As Single = Single.Parse(lblAngle.Text) * PI / 180.0
        Dim sin_theta As Single = Sin(theta)
        Dim cos_theta As Single = Cos(theta)
        Dim X As Single
        Dim Y As Single
        For i = 0 To 3
            X = corners(i).X
            Y = corners(i).Y
            corners(i).X = X * cos_theta + Y * sin_theta
            corners(i).Y = -X * sin_theta + Y * cos_theta
        Next i
        Dim xmin As Single = corners(0).X
        Dim ymin As Single = corners(0).Y
        For i = 1 To 3
            If xmin > corners(i).X Then xmin = corners(i).X
            If ymin > corners(i).Y Then xmin = corners(i).Y
        Next i
        For i = 0 To 3
            corners(i).X -= xmin
            corners(i).Y -= ymin
        Next i
        Dim bm_out As New Bitmap(CInt(-2 * xmin), CInt(-2 * ymin))
        Dim gr_out As Graphics = Graphics.FromImage(bm_out)
        ReDim Preserve corners(2)
        gr_out.DrawImage(bm_in, corners)
        picCar.Image = bm_out
    End Sub

    Private Sub Form2_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown
        Select Case e.KeyCode
            Case Keys.Left
                lblAngle.Text -= 1
                If lblAngle.Text < 0 Then
                    lblAngle.Text = 359
                End If
        End Select
        Select Case e.KeyCode
            Case Keys.Right
                lblAngle.Text += 1
                If lblAngle.Text > 359 Then
                    lblAngle.Text = 0
                End If
        End Select
        Select Case e.KeyCode
            Case Keys.Escape
                End
        End Select
        Select Case e.KeyCode
            Case Keys.Up

        End Select
    End Sub
End Class

Thanks in advance.