Most people die in Arma because they rush in. I can't say how much success you'll have if you take it slow, but i can guarantee you, you will die if you rush in. When you get to the AO, try to find a good vantage point and scope it out, see where enemies are, which way they are heading, and either try to avoid them or ambush them, I'll warn you that ambushing large groups isn't a great strategy, they lock you down with continuous fire and you cant peek out to fire back, god forbid if you're in the open.
Another thing to do, if you see a groups of enemy infantry, mark them on your map as EI, so your team mates can see where they are and plan accordingly.
I would highly recommend playing through the tutorials, they give some pretty valuable tips and tactical information that can save your ass in a pinch.
Something else that is pretty useful, is always carry a hand full of frag grenades and smoke on you (I normally run 2x frag, 2x white smoke and 2x coloured smoke) it's saved me on more than a few occasions. Even if you have to take one less mag to make room for it in your vest, it can be extremely useful.
Well that's all of my protips today, if you want any advice on a specific area, hit me up and i'll see what i can do!