Where to put GL.Rotate in Windows App?

private void glControl1_Paint(object sender, PaintEventArgs e)
{
            GL.MatrixMode(MatrixMode.Modelview);
            GL.Translate(0, 0, -500);
            GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
            GL.LoadMatrix(ref cameraMatrix);
 
            GL.Rotate(camera_rotationY, 0, 1, 0); // Add the Y-rotation
            GL.Rotate(camera_rotationZ, 0, 0, 1); // Add the Z-rotation
 
            glControl1.SwapBuffers();
}
 
private void glControl1_KeyDown(object sender, KeyEventArgs e)
{
            ...
 
            if (e.KeyCode == Keys.Up)
            {
                camera_rotationZ -= 5;
            }
 
            if (e.KeyCode == Keys.Down)
            {
                camera_rotationZ += 5;
            }
 
            if (e.KeyCode == Keys.Left)
            {
                camera_rotationY -= 5;
            }
 
            if (e.KeyCode == Keys.Right)
            {
                camera_rotationY += 5;
            }
 
            Vector3 lookatPoint = new Vector3((float)Math.Cos(facing), (float)Math.Sin(pitch / 2), (float)Math.Sin(facing));
            cameraMatrix = Matrix4.LookAt(location, location + lookatPoint, up);
 
            glControl1.Invalidate();
}