For "physical notes" of Bitcoins you need a centralized service, that garants the worth of the "Bitcoin note" and that it wont be used after selling by the seller.  There are two possibilities of creating Bitcoin notes. The first one is handing out the whole wallets for a certain amount with the private key. The second is a kinde of gift card or coin and a service, that hands out the Bitcoin and transfers the amount to your wallet. But you need a third party for it.