With Pinterest, it is very important to act like a real person and not like a bot. Following 500 people will not get you the followbacks that will actually convert. Also, you need to have more boards as 3 is way too few. It looks spammy if you only have 3 related boards with posts that all link to your money site. I generally recommend having 6-10 boards and having them in several different niches. Look at one of your followers and see how many boards they have on their account and try to mimic this.
For posts in those boards, don't try to link everything back to your moneysite until after you have gained plenty of followers. Again, this type of activity looks spammy and will keep others from following you. A good recommendation would be to have only around 10% of your pins link back to your website. Once you have around 300 - 500 followers, you can start to safely increase that % up to around 20 - 25%.
Last tip, make sure to interact with others. Don't just re-pin other people's pins but be sure to comment on those pins. This will look more like a real person and you will start to get more followers from people clicking on your profile. Also, your profile picture should be of someone that has interest in those pins that are in your niche. A profile pic of a girl in a bikini will not match a profile that promotes circular saws and DIY home projects.
Good luck with your IM journey!
