Well acctually it's really simple.Every gear has it's lvl(gear's lvl can be upgraded with vio's),when your characters lvl matches you'r gear's lvl then work your ass to hunt bosses for reds.
This solution gives you 75% rate.
Lets say you have a lvl 80 unique helm,and you'r lvl is 80 (should be same lvl but less then 30% at the lvl xp bar) should take you MAX 5 red's to make the helm elite.
From my experience:
At lvl 88 made my elite +12+soc brace to super with 1 red,i was same lvl and 20% at the lvl bar.
At lvl 91 made my elite +12+soc boots super with 3 reds.
At lvl 92 made my elite +12+soc blade super with 2 reds.
Next lvl at lvl 93 going to make super the socketed+12 armor ,at lvl 99 the +12+soc helm,at lvl 101 the +12+soc neck.
Wish me luck to do that with less reds
To make a weapon is hardest,could even take 10 reds or more
by kSharp