First of all, charms. Personally, I recommend Fragile Strength and Fragile Greed. You can get both of these from Leg Eater. If you want to, you can also Overcharm. If you do this, I recommend charms that increase focus gain and spell damage, and remember, overcharming means double damage taken, so be careful.
To Overcharm, try to equip one more charm that requires more than however many charm notches you have left five times.
The location is just above the Greenpath Stag Station. Just go up and kill the Moss Charger, and the two Moss Knights. Then go back down to the Stag Station, rest on the bench, and repeat till you’re satisfied.
With Fragile Greed, I got 51 geo per Moss Knight, and 10 geo from the Moss Charger.
Killing the Moss Knights
This section is just how I personally do this part.
For the Knights, I personally fire Vengeful Spirit at em twice, then just go back and forth dodging and striking with the Nail.(Wait until just after the Knight swings, you can get two hits if you’re quick).