This. I have yet to play Gears online after owning the game since release. I was about to play it once when I thought it supported Guests like Halo did. I found out it did not and I was dismayed. My friend and I opted to play co-op story mode isntead.
I obviously couldn't find how. I tried setting up a player match but my friend and I could not find the option. True, I have never played Gears mulit-playe either so I was not familiar with the interface whatsoever.
Yah it was hard to figure out but you just have to sign in as a guest with the x button while in the versus menu.
You should try it, it's tough as shit at first but once you get used to it it's so much fun