Modding for Dragon age on Mac

Hey Guys!

I have Dragon age Origins on my PS3 and wanted to experience what it would be like on Mac. My brother also has it on his windows computer. However, looking at all his intresting mods i have wanted to experience the same thing but on my mac. The only problem is i have next to no idea in how to do it. Ive looked at videos and searched through lots of different websites and trying to understand dazip files and 7 zip files and everything literally goes right over my head. Whenever i try to do something and it looks like it might work unfortuantly it dosent. I also have modazipin downloaded. Is there any chance someone could give me an idiots version on how to download mods as my brother is getting very annoyed with me pinching his computer to play the game! 

Thank you!