I'm aware of what a sling looks like, you can find it in cows as well. The 2nd cow kill I took home was one sling. First kill was runescape cheap gold an airstaff. Also, questing is a problem, I SUCK when it comes to quests. I'm not certain of which quests to do, and if they're really long, I get bored easily. So basically questing for full rune armor as well as melee training are my biggest issues.
You can't simply transform money into more. Simply do herby runs practice profitable techniques like hunter and fletch yewlongs, or something similar. Someone said 99 fishing you could do it Just make sure that you catch rocktail between 90 and 99. Yes, you can, but it is slow and long dependent on the point at which you begin and how determined you are you can transform 1gp into 1B in time.
The way I'd do it even though you've 15 million is to invest in something that oscillates between a high and low the price, but it is snared in the middle by its alch price; at this point you don't want to be taking huge risks when you invest your money but building it slowly and 15M which is an excellent amount could yield around 400k of profit for each session of Green Chaps as an example.
Since they never drop below 2200 for very long due to their ALCH value that is 2380, you could buy them for 2200-2250, and sell for 2300-2350. This isn't the fastest method available, however it's reliable, for those who are members and want to go to the more exotic goods like black chaps for 5400, and selling them at more than 6000, but if you fail to time it properly, you could end up with stock for a while.
Do not buy red dragonhide, as it does not sell well and also avoid seeds like they're the scourge. I have lost an absolute fortune with them. The trick is to go to the graph that shows the 180-day period and study the patterns that bounce constantly between two points and purchase and sell before they reach them, it takes some practice , but eventually it is possible to make huge profits of between 1-2 million everyday...do some woodcutting or slaying while you are at it so you are not wasting time either.
Herb running (in terms of) is the running that runs between all of the herb patches typically in the most time efficent way possible. It takes a while to master a decent route running among the ones in the undulating swamp (forget it's name) or the one in draynor manor The one north of ardy, the one in Catherby, and (if the quest is complete) the patch at Trollheim.
The goal is planting (usually) which is the best-performing herb seed that produces the most profit when harvested. I'm not entirely sure about the best place to start or even the current price. However, I would buy runescape 3 gold probably not recommend doing it at your level until you've got additional herb options.