Are you monthly or prepaid?? If you are prepaid then your account was set up right at registration, but if you are monthly, then you would have recieved an email at the time of activation with instructions on how to set up the account.
Is your account set up? You should be able to sign in right from that moment.
If it's not set up search Koodo in your email and look through the emails to find the one with your self serve activation instructions.