Many employers require their potential hires to be proficient in Excel. There are a number of things you can do to acquire and demonstrate proficiency in excel.
Work through the models in the Oltheten & Waspi 2012 textbook as you work through the course. These models are designed to help you better understand the material as well as to help you develop your excel skills.
Save as *.xlam on your computer. If you open it directly into Excel, Microsoft will convert it to an *.xlsm file. If you end up with an *.xlsm file, save as an excel add-in.
Earn a Proficiency in Excel Certificate from the Margolis Markets Information Lab. In order to claim proficiency in Excel on your resume you must earn the proficiency by completing the Excel program at MMIL.