First you get by doing the quest for the first time, the secound you can trade for 3 Tokens.
First Earring/Ring you get from the Quest. If you want a 2nd, you need to have 3 Tokens in your inventory, the NPC on the left of the quest giver will have a quest for you where you trade your 3 tokens for another Earring/Ring.
Now you need 5 Tokens in your inventory + the Earring/Ring and the NPC will have a new Quest which let you upgrade your Earring/Ring.
BE CAREFULL! He stil offer the 3 Token for a 3AP Earring/Ring quest, i have a frined he made 3 normal Rings because he clicked wrong/to fast.
Now you need 10 Tokens to upgrade your Earring/Ring to a 5AP one.
This quests can be repeated every hour! Yes, if you grind it hole day you can make pretty easy 5AP Earrings/Rings. And while doing that you automaticly farm for Witch Earring and Mark of Shadow. I dont understand the difference here or if the Witch Earring/Mark of Shadow has hidden stats but its nice to start with.
Theres another quest in calpheon which let you collect another token and this one can be traded for a Necklace with starting 4AP.
You need 5 Tokens for the 4AP Necklace, another 10 Tokens for the 1st upgrade (Dunno stats) and another 20 Tokens for the last Upgrade.
Pretty neat after getting lvl 50. I got the quests after finishing my Black spirit quests also read on some sites thats this quests is a RNG-Quest and cannot triggered or forced to show up but once unlocked you can do it every hour.

All credit goes to "CaryaLoL" (https://www.reddit.com/r/blackdesertonline/comments/49sami/earringsrings_of_dim_magical_power_can_you_get_a/)