I'm gonna spoil it, I reached as high as 90m this season, rn I'm on 20mil. It's XP farm. So you gather your spawner (ideally 10-15 spawner) and get your insquitive sword. I started with ham farm, when I reach around 1,5 mil from the ham farm, I finally can afford a insquitive II sword, so I started grinding EXP. Now idk the price of the exp in the start of the season. But I was on jartex mostly in beetween the season. 1m xp sell around 1.5-2.5 mil. Use that money to buy another insquitive sword, either to combine your current sword with the new one or just buy a higher level of insquitive, you should have mills now, now if you're rich enough and have 20 mil at your disposal. You almost likely can afford everything listed on /ah. Go /ah and learn the price for each item, if there's someone selling an item lower than it averages price, buy it and resell it.
tl;dr
Ham Farm -> Buy Insquitive -> Farm more XP -> sell xp -> buy higher insquitive -> farm more XP -> sell xp -> do trading on /ah, buy cheap item and sell it with a higher price ( thing I resell are XPs, E-Gaps, Gset, Custom Enchant book, Sword, Grinding Sword, Voucher.
Also do /cf for quick money. Cfing 40m is the thing that make me reach 90m
My english sucks I know, See ya