I'm gonna assume you got your login details.. well, whatever.. new acc. sounds inconvenient.
(average player here)
I remember doing similar.. I wanted to play today not tommorow, ie install from dvd(s?)
No multiplayer without the.. 6gb's of patches out now? oh yeah that's right.. BF3 expansion information/maps n all, regardless of whether you have access to them. assist compatibility between client installs. So multiplayer is off the cards till your cap handles.. or lugg pc somewhere, dl patches.
Set browser to offline mode (or disconnect internet) Launch BF3 from origin (it has an offline mode possibly)
Browser window pops up.. Play single player.. mission menu's are all in the browser window, Launch game.
Game launches.. video/audio etc options are within game. Best of luck with it/
Can't whinge about patch files, every multiplayer game that is well maintained/popular has comparable.. though 6gb is a lot.