keeping your tan depends on your type of skin.
but you can always help it along by after everyday put dove holiday moisturiser on, but remeber there is a hint of fake tan, so rub in it evenly.
peeling, is dead skin, so theres not really much you can do to stop that, just keep moisturising, & if you use the dove holiday moisturiser, you can kill to birds with one stone :)
It's going to eventually peel. It's dead skin.
You can keep going under the sun to regain your tan but thats all I know.