You can not simply turn OSRS gold money into more cash. Just do herby runs, train profitable abilities like hunter, fletch yew longs, anything similar. Someone said 99 fishing, that would probably do it, just make sure you fish rocktail 90-99. Hell yes you can, however it is slow and a long road, depending on where you begin and how dedicated you are you can flip 1gp into 1B punctually.

The way I'd do it though today you've got 15M is purchase something that pops up and down in price but which is caught in the base by its alch worth; at this point you do not want to be taking big risks with your pool of money but constructing it gradually and 15M that's a fantastic sum will gain you about 400k gain on every cycle of green chaps for example. As they do not fall below 2200 for very long since they've got an alch worth of 2380 you can buy at 2200-2250 and sell for 2300-2350.

It's not the fastest method out there but it is consistent, if you're a member you may visit more exotic items like black chaps, buying at 5400 and selling at 6000+ but if you do not time well it's possible to end up holding inventory for a Buy 2107 runescape gold while. Stay away from red dragonhide, it doesn't sell well and avoid seeds like they're the plague, I've lost a complete fortune on them. The trick is to visit the 180 day chart and look at what bounces always between two things and buy and sell until they reach themit takes some practice but in time it is likely to make fantastic profits of 1-2M everyday. . .do some slayer or woodcutting in precisely the same time so you are not wasting time .