Update: I cannot level down items to level 40 for level 20 character so Druidic robe is ruled out and other such items but that’s ok because crystal crafting can still allow you Ignore Resist at level 20 character on level 40 gear as well as other affixes for high damage solo EXP farming.
#At level 1
Firstly you have the ascended character at level 1 when you clicked the perk you wanted and your character will end up having the level 1 gear equipped automatically.
The level 100 items remain safely in the inventory and you need your inventory not to be full before ascension as it doesn’t let you with full inventory.
When the ascended character is level 1 , grind that character to level 20 with the hirling who has level 100 gear to level 20.
No zircons required at this point since level 20 is fairly easy even for eternal ascension. Although you can add quest stones on level 1 gears if you keep them and if you use hirling to level him/her up all the way to 50.
#At level 20
Once the character reaches level 20, this is the best time to level up solo without hirling since it’s far quicker but if you do decide to keep hirling, they would also have quest stones.
With the level 40 loot you found on floor 40 or so with at least a socket , use the 6 zircons for the 6 quest stones for 200% EXP Gain. This gear doesn’t even have to be legend as well.
Then with that level 40 gear for level 20 character, add amethyst for sets like Plagued , Momentum+Adventurer , Arcanist , ascendant, and any good set for a working level 40 build for EXP farming.
The crystal affixes are also included as well as ruby for legend affixes such as Ignore Resist , Blight , etc.
Also epic affixes like WD and ED.
You can even determine talents with Citrine and Natures with Beryl for extra power.
Once you got a working level 40 gear for level 20 character, play a floor around floor 101 or close to it if you can and do packsize % maps. In those packsize maps, group the enemies together and let them be poisoned with toxic poison clouds to kill them quickly for a huge surge of EXP and you’ll reach level 50 quickly, even in eternal ascension.
You can do this on mythic 3 and still do fine.
#At level 50
Once you reached level 50, this is where you equip your level 100 EXP grinding gear and you can do this solo or using hirlings.
A good example is this one:
Optional: You can add Nadroji bonus on the chest and Nadroji . Another thing is adding Epiphany set affix if you reached floor 600 epic difficulty to get up to 250% EXP Gain .
Also if you are using hirlings, having 6× quest stones on both characters. It used to be that hirling wasn’t viable because of negative EXP Gain but that’s less likely as hirling already adds 100%+ exp gain to make up for it. Optional is Epiphany and Nadroji Bonus.