Extending wifi range with old TP-Link router

[#1]

Due to the only location where i can place the router (Technicolor TG582n) and the thickness of my house walls, i get poor wifi reception in certain area's of my house.
to extend the wifi's range, i would like to add an old TP-Link router (TL-WR740N) and powerline adapters that i have laying around gathering dust. i already use a powerline adapter from the router for my HTPC.
my question is, what are the settings i need to apply on both routers, to make the TP-Link router mirror the plusnet router and extend the wifi range?

[#2]

Channel, SSID, encryption key... should be about it.
IF they're both acting as identical access points then your wireless devices should switch automatically between them as needed.
On the 2nd router though you need to login and disable DHCP and set your DNS to the ip of the primary router.

[#3]

Quote

IF they're both acting as identical access points then your wireless devices should switch automatically between them as needed.

I wish that was the case, should and will are 2 very different things when auto-switching in concerned. You have to spend a good amount of money on equipment for this sort of system to work properly