When you hide a sheet using hidden or very hidden and then you want
to use a macro to view the sheet you will need to tell the procedure
to un-hide the sheet first, to do this use the following code

Private Sub CommandButton1_Click()
Sheets("instructions").Visible = True
Sheets("instructions").Select

End Sub

Then put the following code in the instructions sheet

Sub worksheet_deactivate()
Sheets("instructions").Visible = xlSheetVeryHidden

End Sub

And when you click off the sheet it will hide it again.
If you passworded the sheet you would have to do the same for the
password as for the hidden sheet.