Mapping Lan traffic to specific WAN

Installing and Using OpenWrt Network and Wireless Configuration
6

Trying to recreate the solution from here , I have setup 2 WAN pppoe and 2 LAN with DHCP each but lost on how to map each to seperate WAN

config interface 'lan'
        option type 'bridge'
        option ifname 'eth1.1'
        option proto 'static'
        option ipaddr '192.168.1.1'
        option netmask '255.255.255.0'
        option ip6assign '60'
        option metric '10'

config interface 'wan'
        option ifname 'eth0'
        option proto 'pppoe'
        option username 'wan0user'
        option password '123456'
        option ipv6 'auto'
        option keepalive '5 5'
        option peerdns '0'
        option dns '8.8.8.8 8.8.4.4'

config interface 'WAN1'
        option proto 'pppoe'
        option ifname 'eth1'
        option username 'wan1user'
        option password '123456'
        option keepalive '0'
        option delegate '0'
        option ipv6 '0'

config interface 'LAN1'
        option type 'bridge'
        option proto 'static'
        option ifname 'eth1.1'
        option delegate '0'
        option ipaddr '192.168.2.1'
        option netmask '255.255.255.0'
        option metric '20'