I did a mix between doing the included tutorials, several books from packtpub.com and also pure C++ and C# tutorials (just to get a get a solid basis about coding). I fell in love with Visual Studio 2015. <3
Here's something that I notice about people who no longer need to whore after tutorials or beg for wet-nursing in public: Almost all of them either have a secondary background in another language, or come from another language.
Often this other language is stricter and doesn't tolerate the kind of crap that GML typically puts up with under the banner of accessibility. Coincidence? I think not, it does take a strict master to make good students.