Burn a back up disc

Hello,
I bought a new acer computor a couple of days ago and had no problem setting it up apart from when I tried to create a back up disc which is recommended and the system takes you through step by step,the problem was I had a faulty 2nd disc so had to cancel the back up. I now have some new disc's but how do I get back to the point where I can burn a recovery to factory settings back up disc.
All help welcomed