I assume you have a lev 60 hero and a minimum of 5 million gold.
This guide is for freh lev60 ROS starters, who don't have much luck in the first few playing hours and need a good lev70 starting wepaon. If you are lucky in the first few hours at level 60 and firnd some good weapon (better then mine which I posted at the end of the guide) then you can skip this guide.
1. play the campaign act 5 and lev to 70.
You should pick up every item and salvage it at the blacksmith if you don't need it.
Playing the highest difficult level, which you can afford.
2. choose the weapon you want to craft
http://eu.battle.net/d3/en/artisan/blacksmith/recipe/
click Advanced Filter
click tab rare
select Weapon (One-Handed, Two-Handed, Ranged)
select training
click on column req until it's sorted from high to low
=> then you have all lev 70 weapons which you can craft really easy
Now choose one of these weapons, which you want to start.
Look into the column of the level of the blacksmith.
3. Play the adventure mode at highest level you can afford and do the bountys
You should pick up every item and salvage it at the blacksmith if you don't need it.
Play aslong as you have a minimum of 120 Reusable Parts, 190 Arcane Dust and 150 Veiled Crystal and a minimum of 10 Death's Breath. If you want to craft a class specific item like a daibo, fist Weapon or ranged weapon you need some more death breath.
4. level your blacksmith to the required level of the blacksmith.
Therefore you need some of your Death Breath, but don't spent all for leveling the blacksmith if you have reached the required level, you need it later. Later in the game process you will have enough Death Breath to level your blacksmith.
5. craft your choosed weapon until you get one or two (depends who much you need) with following 4 primary stats
x-y damage
core stat (strength, intellect, dexterity)
socket or +x% damage or increased attack speed (if your class / skills profit from attack speed)
4th random primary stat
If you are unlucky you must farm and craft more by playing the game.
6. level your mystic
7. Enchant your crafted weapons
We want
socket
+x% damage or increased attack speed
Therefore we must enchant our 4th random primary stat.
Everytime you enchant an item again it costs more gold. So if we don't get our expected result until the goldcosts reach 150k, we stop it and craft a new item.
For enchanting a weapon we need many
Death's Breath.
To get Death's Breath you must kill elites, you can get it by playing the game the usual way or can explicit farm for it. How you can explicit farm it can you find in this guide.
Only at the start of the game you will have a high demand for Death's Breath. Later you find enough by playing the game and killing more elites at higher difficulty.
7. Socket your Weapon with Marquies Emerald
(or Marquise Ruby, depends on class & skills, but most will take the Emerald)
You find this gems by playing the game. In higher difficulty you will find Imperial gems.
If you have enough gold, you can spent your gold in upgrading your gems, but I recommend to do it later and always safe some money.
8. You can transmogrification your weapon
If you want you can change the look of your weapon with trannsmogrification at the mystic. It will only cost some gold.
The weapon is finished and it should look like mine.
These are good starting weapons for your first lev 70 hero.
