For a skill guide, check out the stickied thread at the top of this forum.
For build though a lot changes when you hit Pando. The mobs hit far harder, they crit more often, and they are harder to hit.
With 50 dex you will be okay in CL, but as soon as you hit Pando you will need a lot more - at least 200 (though I prefer a it more). A lot your best skills are dex based, and without more dex they will miss often.
You can pick up more dex by adding lapis - 5 level 5 shrewd would give you an extra 100 dex, which would go a long way to your target (or if you have more money, 5 level 6 shrewd would get you there). Dual shrewds can also be useful - there is one that gives dex and defence.