tab page header color

private void tabControl1_DrawItem(object sender, DrawItemEventArgs e)
{
    // This event is called once for each tab button in your tab control

    // First paint the background with a color based on the current tab

   // e.Index is the index of the tab in the TabPages collection.
    switch (e.Index )
    {
        case 0:
            e.Graphics.FillRectangle(new SolidBrush(Color.Red), e.Bounds);
            break;
        case 1:
            e.Graphics.FillRectangle(new SolidBrush(Color.Blue), e.Bounds);
            break;
        default:
            break;
    }

    // Then draw the current tab button text
    Rectangle paddedBounds=e.Bounds;
    paddedBounds.Inflate(-2,-2);
    e.Graphics.DrawString(tabControl1.TabPages[e.Index].Text, this.Font, SystemBrushes.HighlightText, paddedBounds);

}

Setting the DrawMode to 'OwnerDrawnFixed' means each tab button has to be the same size (ie Fixed).

However if you want to change the size of all tab buttons, you can set the tab control's SizeMode property to 'Fixed' and then change the ItemSize property.

Thanks & Regard
Sham :)