Once logged into your NEO ONE account, from the home page, select the account from which you wish to make the transfer. Once the account is opened, you will see the option to ADD MONEY. Select the option you want, whether INTERNAL or EXTERNAL.
For internal transactions you must share your Account ID.
For external transactions you must share your IBAN.
Remember that internal transfers are between NEO ONE users.
And for external transfers it is via SEPA.