How to play xbox live on halo 3 with out hosting games just finding and joining??

[mitch g]

I wrote a question like 10 mins ago but it still doesnt work, Can someone please give me step by step instruction starting form the halo 3 main menu (i have my xbox live working) PLease I need step by step and it says that there like 300000 people on but how do i join games

 

[Smithy55]

Okay. Main menu > Xbox Live > matchmaking (then choose a variant i.e team slayer big team battle) then press start

if you meen oin a custom match then bungie haven't made this possible but there are alot of rumors going on about it despite bungie's statements.