I like how everyone says Buy low sell high
wonder who buy's high and sells low
as for me-
Im a little addicted to gambling in game XD but it has paid off really nicely on more than one occasion. I would suggest making one big bet every once in a while over a lot of smaller bets. smaller bets will keep you with money so you dont go completely broke but you often end up even or not making a substantial profit whats the point in the gambling in the first place if your not making a big profit
Mining is a good way to make money, I normally sell all my poor and medium ore and smelt any high and very high ore I get. this way im working on a refining skill (although very slowly) while still getting some money for whatever I might need, most like gambling.
I spent TONS of time vortex bossing when I was right around chaos stats I got a group together with some friends in game and we would boss for a couple hours almost every night. but when I was bossing I used to be able to get 8.5m for an Old claw and like 6m for an Old daemon heart and all the EE san drops were pretty pricey, but my bossing group kinda messed that up for other people.
and if your dedicated enough to it you are bound to get some nice things ive personally found 3 armors and 1 weapon from vortex all of these will catch you a rough 5m or so depending on the item
Easiest gathering skill ever. put on the auto swing "feature" turn up the volume on nexus so you can barely hear the annoying thwacking of the axe. learn the sounds of swinging without an axe swinging at air and swinging at a tree then you dont even have to look at your screen and dont have to worry about being caught autoing by the nexus nazis
also this skill is really quick to level up in compared to mining ive spent 1/2 as much time woodcutting as mining and im an expert woodcutter and a talented miner