Don't ask where something is...
Look first. Usually it's right in front of you. Also, we can't always be looking at your half of the screen if we're playing against each other. Also, when we tell you "to the left of you" don't be like "nope, don't see it. Oh!" We'll just sigh long and deep...
Don't ever refer to the in an in game object as "that thingey"
It's disrespectful. It makes it seem like you're making a joke out of a game that we are already well are we take far too seriously. When you say that thingey it makes us realize you're playing this game on a lark--you don't have the intention of actually learning and getting good like we do--so fake it.
If your computer freezes...try restarting it
Don't freak out. Computers freeze from time to time. Restart fixes most problems when it comes to computers so just try that first.
If you get the best loot and its class specific and/or you're not a high enough level to use it...give it to someone else
This probably won't apply to most girls who are just gaming once with their boyfriend to be nice but in mmos only one person can grab the stuff that a boss npc drops and usually its based on everyone rolling a dice. if you pick first dont grab the thing you can't use. it's just wrong.
Find out the armor/damage specs...never say you chose to equip that armor/weapon because it's "pretty"
Again, at least try to get into it. He'll appreciate you knowing a thing or two. It's the equivalent of you going to the mall with your boyfriend and asking which one and him looking you dead in the face and saying they look exactly the same to me.
If you're in last and your boyfriend is in second...nothing you're going through matters
Especially in a racing game if he has a chance of winning and you have no chance at all then why does it really matter that you're going in reverse? When you insist that he helps you, he will lose and you will still be in last.
There are probably a lot more, but this will help get you started as you go further than most girls will go in order to bond with your boyfriend whre no girl has ever bonded before...