It depends on if you want to spend real money or not. If you want to donate for an easy method, then the Nether island is a great way as soul sand sells at spawn for $75 each soul sand, but the problem with this is that you can't be added or have your own island. The safest way to get money without spawners in my opinion is a cactus farm or crop farms. The cactus farm is the same as one of those mob farms in factions that you'd use to farm money, but the cactus farm is a cheap way to get money because it can be built upon and is fully automatic. The other way, crop farms, require the use of hard labor and you'd definitely need the drive to actually farm.
When you start, the best method in my opinion is farming coco beans, wheat and carrots. Then you can sell cookies and carrots which will get you some money. Later you can build a cactus farm, but it can be expensive with all the sand you'll need. Cactus is one of the best things because you can just walk around on your island while cactus is coming in.
Since literally everyone's response to making a cactus farm is "Too big" or "Too expensive" start off small with 1 row of cacti and work your way up from hacking. I definitely think that's the fastest way, unless you want to buy money...
Best way to make money hummm.. Just starting out Pigman farm is the way to go. gold,flesh and tons of xp. Best part is it's free and you don't need much money to build. After that cactus farm at the right size can make u a billionaire.....
