Before you blow dry or anything else, use a serum (I use CHI). It protects your hair from heat. But the real reason it looked so good is prob. b/c of the blow dry. You need to blow dry using a big round brush or paddle brush in sections (clip your hair up and dry section by section).
Make sure your hair is COMPLETELY dry (if it's not, humidity will attack it). Spray iron guard on before straightening, then go to town using a CHI straightener. You also have to do that section by section. It will take a while to do this process until you get used to it, but your hair will look awesome. It takes time to look good

Spray shine spray on when you're done!