Gear info for a newbie
Well, I assume you are still leveling to 80 and you will acquire sufficient armor through quests, events, crafting and your storyline. If you aren’t doing all of those, I would recommend to start.
At 80, there are many ways to acquire your exotic set. You can craft a set, once you get the appropriate crafting skill to 400. If you horde Karma (which you can do or spend it on really good armor as you level, really your choice), you will have enough to start buying exotic pieces in Orr. And, as you already know, you can start running dungeons for tokens or drops.
I either buy mine at the trading company or i farm karma and get karma gear…. im not much of a crafter XD
Thank you for the tips, but what is the optimal gear and gemstones to be had to run the lvl 30 – 75 story mode and explorable mode dungeons(I understand that for Arah I can get the exotic set).
That is a really broad question. I don’t think anyone is going to be able to give you advice for an “optimal” set for many reasons. We don’t know your class, your level (30-75 covers a lot of ground) and probably most importantly, your playstyle.
You level very quickly in this game. Which means you will go through a lot of different armor just as quickly. I wouldn’t worry too much about building an optimal set at this point.
If you are concerned about stats, again not knowing some key info to make a certain recommendation, I would say to focus on upgrades that improve defense and power. Those are two very generic stats that first time players probably wont go wrong with getting while leveling.
But, again, you will be going through armor quickly during that level span. In all honestly, just go with a piece that is a little better then what you are wearing. By the time you figure out if it works or not, you will probably have leveled out of it anyways. 
Oh! Forgot to mention the class and lvl… I have a lvl 33 necromancer atm.
Just make sure to check each Heart vendor after you do a Heart and buy and Green gear he has. Also, you get good level appropriate gear from your Storyline.
Other than that, you can check the TP for gear, but it will get replaced quickly, so there’s not really much point.
And good luck getting into a dungeon at level 35-40. Looks like most AC story runs want level 80s.
Cheers.
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