You simply need to Log in to your account and select 'Withdrawals' to move cash to your nominated bank account. If you have recently sold investments you cannot withdraw the proceeds until after the settlement day shown on your contract note.
You should receive the funds within five working days. However, the withdrawal may take longer if you have changed your bank account or if this is your first withdrawal as we may need to verify your bank account details.
Please note that once money has been taken out of your ISA, it cannot be paid back in if you have reached the annual ISA allowance limit for the current tax year.