Since I started playing RS I have always made my money by skills, woodcutting, mining, runecrafting etc.
But with every1 making millions merchanting, I decided to give it a try. I sat in Varrock bank world 1 for about an hour, bought 1k iron for 50 each. I just sold the 1k iron for 100k! Now I know thats not a lot of money by any means, but its a start! Im hoping to make a mil by sunday. Ive got about 500k already, so it shouldnt be to hard.