Mac File Sharing for Networking Novice

My husband and I run small filmmaking business from our home. We have a bunch of Macs, old and brand new. I understand that file permissions etc. are important, but in our case we would like the whole system to be wide open for the two of us and our several computers all on the same WiFi network.

I read a similar question, that eventually got into terminal and ACE or something like that. Isn't there an easier way? We have resorted to sneaker net.

Where can I find a step by step explanation of this?