You can hide sheet via Format > Sheet > Hide.
You can also make sheet 'very hidden' - not to unhide with excel interface. To do it without coding, display VB editor (Tools > Macro > Visual Basic Editor). Click sheet's icon in Project Explorer window, in Properties window set 'Visible' property to 'xlSheetVeryHidden'.
If you need more advanced navigation, you can reserve a part of each page for navigation buttons with assigned macros. The code behind each button, with hidding sheets:
Sheets("NewSheetName").Visible=xlSheetVisible
Sheets("NewSheetName").Activate
Sheets("OldSheetName").Visible=xlSheetHidden ' or =xlSheetVeryHidden
You can navigate workbook with hidden sheet tabs, in this case it is enough to activate sheet.
combo