Hello! First you need some basic routing skills for you to solve this. You should place the routers within the same network, then add routes with equal metrics, therefore if one link goes down, the routers should communicate with each other so that they pass traffic to the available gateway (in Cisco routers, CDP does this-it updates neighbouring routers of the status of one another). For eg if you have router a and b, incase router a is down, router a will receive traffic from the client pcs and since its status is down it will route traffic to router b, it knows the status of b, up. When both links are up, you can use static routes to direct traffic to the interfaces on your routers depending on the size of your network. This can balance your load.
--------------------------- Both optimists and pessimists are important in technology. The optimist invented the aeroplane; the pessimist invented the parachute. Regards, Hesbon Ongira Nairobi, Kenya.