How do you host a game on MW2?

You Can't. Only If You Have A Good Computer Operating System; They Might Choose You Randomly On Consles...Im Not Sure. There Is No Way To Be The Host Intentionally Besides On Private Match

Go to "Clan Tag'' and see if you are the host. Input IW and it would either say not

authorized to have this clan tag or something but if it allows you to have it then you are

hosting. :)