I am a DELE certified Spanish trainer and translator with more than 5 years of experience. I use multiple resources and help my students go a LOT beyond the standard textbook and sound like native Spanish speakers. I use my own notes, various YouTube channels for listening exercises for accent practice in addition to the textbooks like Aulas, Nuevo Ven etc.
I also work with various companies and working professionals and modify the courses according to the requirements of their industrial sector and country of business (eg I created a customized course related to banking sector for employees of Barclays Bank who had to move to Chile)
