Help me with dual wan

[ginosteel]

have tried with some tutorials but i could not do anything
i have
WAN with ISP public IP
LAN with public IPs and OPT1 ADSL behind a router with private IPs or if i want i can put a public IP from the same class
I am using DHCP with Captive portal for LAN
and i want a simple config:

All the http from LAN routed to OPT1 and the rest to WAN
I have tried a lot of rules in firewall but still nothing
I cannot belive how others can do a hard config working and I could`t made one easy config.
Can someone pls give me a detalied step by step configuration

[Veni]

You need to add a rule on the LAN NIC.

1. Firewall/Rules/LAN.
2. Add new rule.
3. Interface: LAN.
4. Protocol: TCP.
5. Source type: LAN Subnet
6. Destination port range from: HTTP.
7. Gateway: OPT1-OPT1.
8. Save.
9. Move rule to top.
10. Apply changes.
11. Wait couple of seconds.
12. Try to browse to http://www.whatsmyip.net and see if it shows you correct ip address.