Instrumentation engineer

I have completed B.E. Instrumentation & control. I have worked in control panel manufacturing company for 3 years as a project enginner,after that i worked in emerson for 1 year as a purchase engineer ,currently working in elevetor manufacturing company as a sr.purchase engineer. now I would like to change my carrier. I want to work in consultancy firm on projects.Give advice how can I change. What courses I can join for getting job in consultancy?