You can't write a guide for winscp, all you do is add the ip, user and pass and connect. It's not rocket science.
You have either left the centos firewall enabled or you have screwed your network config by adding the exact ip addresses you saw in the guide which is wrong. You must use ip addresses that are correct for your network.
Test connectivity with pings. You won't be able to connect to centos unless you can ping it.