I think you did and excellent job if you did all alone. Actually a lot of exercise in my method are similar, except for the respiratory stuff, that it's not important for us. The main difference is that we try to think sound per sound. It's more easy in Italian because sounds and letters are the same so for example Italy, you will first pronounce I - T - A - L - Y and then you will learn how to join the letters and then how to go more quick in phrases and became more natural. The key is that if you say one single sound you don't stutter, so think sound per sound It's a very short explanation but this is the key Maybe you will use also this in your method