A method for putting into operation a processor smart card in a network for communication, preferably in a GSM network, wherein the card user must identify himself with respect to the processor smart card (SIM) by a personal identification number. An application is stored on the smart card to control the execution upon the first use of the processor smart card by the card user. The application is used to transmit an indication of the first use to the card user. The application is arranged to transmit personal identification numbers for subsequent use of the processor smart card in the network to the first user of the card or to let them be defined by the first user of the card.