After having generated voucher code(s) as described in 6.1, on the VOUCHERS / Manage Vouchers page, click the ‘Go to Codes’ link to display the codes linked to the voucher on the Coupon Codes page. From here you can just copy/paste individual codes and use them as you need.

Alternatively, if you have generated a lot of codes, on the Coupon Codes page for the required voucher, select the required/all codes and choosing ‘Export Coupons’ from the Actions drop-down, you can export a CSV file containing the codes that you can use.