Plenty of Runescape players are looking for ways to make money in Runescape. Being a long time runescape player, one of the things i have learned is that melee is a very good way of making money. This technique will not require you to reach a specific combat level. Any level is fine but 75 + works best. What you will need is a shield. The shield from the Dragon Slayer works. Buy one from the Grand Exchange if you can. It might be cheaper if you get it from other players. You should also have plenty of food. A good melee weapon will help out a lot for the combat. Anti-fire potions will also help you out a lot, but it is not needed. Should you have anti-fire potions you might not need a anti-dragon shield. The Anti-Fire potions can be bought from the Grand Exchange. You can make these potions if you have high herblore skill.
When you are ready go and slay the Green Dragon. If you manage to slay the dragon you can make a lot of money from selling the dragon bone as these sell for a lot. Killing green dragons will make you a lot of money, they drop items like bones, hides and more + money.