HELP – Wirelessly linking 2 Linksys Routers

I have an older WRT54GS (version 1) and the new (black w/antenna placement on the inside) one. I have been trying to connect them WIRELESSLY, (one opposing sides of the house) using the advanced routing. I have changed IP addresses and disabled DHCP like every site tells me. I have spent 3 nights on this and have not found an answer. Right now i have got advanced routing all screwed up. I have reset it to factory defaults for advanced routing only. The subnetmask is 225.225.255.252. Local IP addresses are different. I need a step-by-step process of how to do this. PLEASE HELP ME!!!

Questions…email me at Technogeek-1995@comcast.net