Going for Silver in a rush and skipping Bronze is a terrible idea.
You don't know what kind of game you're going to get. Today, I found my whole squad to be dying every round. Probably because they were beginners leeching for credits. If you end up in one of these, there is no hope to surviving until the end.
What you want to do is make some Bronze games. After you make one, you'll have 15000+ credits, which you will then use to buy Recruit packs to stock up on consumables. Consumables are VERY important. I hate to be playing some random PUG Gold game and see my squad refusing to use medi-gel. It's awful.
Plus, you'll need to ''max'' your Common (blue) items. These include the default weapons, the characters and mods. I was making the mistake of not doing this up until recently. You'll do this to get your default weapons in a better state and most importantly to make your humans look shinier.
On Bronze, play against all enemies on all maps. This will give you a better idea of how enemies try to kill you, so you don't get the bright idea of using melee on a Banhsee.
Try to find a class you feel comfortable with. If you must start as a Soldier, so be it. I started as a Vanguard, but I already had experience from previous games. Vanguard might not be bad for beginning. Spec your Charge for healing your barrier and spam it in dire situations. The Nova that people keep talking about is a high risk/high reward sort of thing. To this day, I get myself killed from trying to do that combo.
After a while, you'll definitely want to upgrade your awesomeness. To do this, research explosions. Fire explosions are among my favourite. And, seeing your name followed by ''(...) Explosion'' on the kill feed is priceless. You'll make the niggas go like: ''Daym dawg, dude just popped an explosion.'' At least that's what I like to think.
I don't think you play on PS3, if you did, I could show you the ropes. Have any questions, ask away!
Qwib