How to Build an Emergency Fund

It's been three weeks now since I've denied myself of personal luxuries. The reason for this is because I realized that I haven't been taking good care of my finances. So for the new year, I promised myself that I will learn how to build an emergency fund and that's exactly what I've been doing. I hope I can create around 3 months worth of expenses for my emergency fund as soon as possible so I can start venturing on investing.