How can you become a member without paying on club penguin?

That is not possible. If you try and cheat to get a CP membership without paying,or refresh the page while cheating to make it think you payed,it may DOUBLE bill you. It probably will never be possible to get a membership for free. The lowest price for membership is 5.95 but you would have to pay online for that price. Six months is 29.95 and twelve months is 57.95. Do not even try getting anything on Club Penguin for free unless Club Penguin decides the item you want is free.