Sub Stylize(frm As Form)
 Dim Con As Control
 For i = 0 To frm.Controls.Count - 1
                Con = frm.Controls(i)
                If TypeOf Con Is TextBox Then Con.ForeColor = Color.Red
                If TypeOf Con Is Button Then Con.FlatStyle = FlatStyle.Flat
 Next
End Sub

This is just an example, setting textbox's forecolor to Red, and buttons style to Flat.