halo reach, how to get lots of credits

halo reach (unlike any other halo games) lets you rank up in a credit system.You get credits for anything and everything you do in halo reach, the more credits you get the more you rank up. Credits can also be used to purchase cool looking armor (armor doesn't affect game play)
so because you get all that cool stuff for earing credits I am going to show you what the best way to earn them is. So the number one way to get credits is to do the daily challenges. If you are not familiar with the daily challenges then visit this link to get a full guide on daily challenges: http://haloreachskillz.blogspot.com/2010/11/halo-reach-daily-challenges-guide.html
so always make sure to do the daily challenges,trust me there is always a big pay off in credits.
Another way of getting a lot of credits is to go into firefight matchmaking and choose score attack it should take about two seconds for it load up different game choice's, vote on whatever you think you can do best on. Stuff like gruntpocalypse and sniper attack give you lots of credits.
in general matchmaking you should choose invasion and any thing you can get a good K.D.R on (for a guide on how to get a good K.D.R visit this link:)
so thats the best ways to get credits in halo reach