Look for an item in game that people seem to want. Find out where that item drops, farm one. Determine if the time it took to farm vs the amount you made is worth while.
Repeat this until you have enough to fire up account #2.
Keep doing this until you have a full group. You can do ALOT with a full group.
Start farming items / selling services that solo and duos cant.
Repeat this until you have enough for another group.
Continue expanding your army, while finding new ways to make krono.
No 1 method works for everyone, ive attempted to explain to a friend of mine exactly what he could do in order to farm krono, hes just not able to do it. Different group make ups, different play times, different skill levels.
The #1 thing you need to remember is that people are always buying things. The more you play the game, and see what others are selling, the more you learn whats desirable. There is not "krono making guide" someone can give to you.