I only get 6GB of memory every month, how do i conserve it?

Okay so i have a wireless hotspot on my iphone. I get 6gb everymonth and i only want to play runescape. Yesterday was my first day using it and i already lost 1GB ( and i know runescape can't take that much).Im thinking it was because while i was playing runescape on my computer, i was watching netflix on my phone. I have sprint btw.

Added (1). The data usage option doesn't tell me anything, all it says is i lost 1GB

Check the data usage option. It will tell you what has been running and using data.

Any media that involves video or games is going to take a lot of bandwidth. If you want to conserve bandwidth, then only use your phones internet for things like checking email and facebook. Text based websites don't take as much memory to download as videos and music and games.

Everything you see on the internet is downloaded. So if you are playing runescape, and you hear music, than that music was downloaded which takes up bandwidth.

Both video games and movie streaming both take up huge amounts of bandwidth… I don't know why you thought runescape wouldn't take up a lot.

Netflix will suck up a ton of bandwith. That 6GB isn't enough for what you want to do with it. And runescape uses a lot more than you think.
You have chosen to do the 2 most "data intensive" things with your 6GB's. They aren't going to last long.
I suggest turning off all other applications on phone and PC that use data. Turn off GPS, turn off location services, youtube and facebook, if you use pandora or other streaming music services that's a big killer too.

BTW Sprint is supposed to offer unlimited data. Check your plan. The upgrade may be worth it.