Setting up a static IP on a Technicolour Gateway TG582n

[#1]

hello there. I have been having strict Nat issues with my xbox one. After many unsuccessful attempts to correct it I finally contacted Plusnet today for advice and help. They couldn't sort the problem themselves ( not great) but sent me links to sites and forums that could help. The site they sent me to is very concise and I was there only the other night actually while trying to sort the problem myself. The issue is that I need to set up a static IP address for my xbox one to start things off and I can't see where I can do that on my Technicolour Gateway router. Has anyone done this before successfully that could help me out?

[#2]

Don't use the PN router anymore, but from memory there was somewhere a tick box for something like "always use same IP for device". Tick that and in theory it "should" (router has been known to be flaky) assign the same IP each time i.e. static for that device.
Sorry i can't be more precise from memory.
If you need more help try asking PN staff for help with their hardware

[#3]

You can actually set the static IP directly through the XBOX ONE too: http://portforward.com/networking/static-ip-xbox-one/
Once you've done that, the IP should be the same each time.