there is a lot of debate always for when the best time to start is...everyone would agree that you should at least have solid foundation to work from and have been training hard for at least a few years...so, you've at least been training for a while from what you told us... i, like many would tell you to wait a few more years since you are still young and your natural testosterone levels should be through the roof and you shouldn't mess with them by taking
steroids at this point and time...but many of us ourselves actually started pretty young, so if you plan on using them you've probably already made up your mind on when you're gonna do them...so, all i can tell you to do is to make sure you educate yourself on them and do them right...you can learn a lot from hanging around this board, so if you're going to wait you can still stick around and learn a lot