Cisco 525 Secure pix firewall configuration problem with NAT,PAT

Dear All,

I am Raktar hussain, working as Network administrator under TCS limited.

i am new guy on PIX firewall. i have no idea to confg. pix.

I have one ISP connected 1800 router to pix and one mlln link guwahati to kolkatta tcs.which also connected to pix.

i have nate configuration to pix.
outside ip come fron isp and converted to to two ethernet port (NAT) one 192.168.1.0/24 series and one is 192.168.2.0/24 series.

another one segment is connected to pix which is 172.16.50.0/24 series (OFC).for distributed network.

my question is i want to reconfigure it, so, please help me any one?