Use indentation, font changes and bullets to make it easy on the eyes, easy to grasp. That said, do not go overboard. Usually, no more than three fonts are used. And use only the basic fonts - Arial and Times Roman with the tasteful application of italics and bold. Do not use fancy fonts.
Employers look for a steady progression of increasing responsibilities.
We recommend organizing your resume by focusing on the titles you have held. Recruiters and HR people are primarily interested in the concise details. Briefly list what products, processes and equipment you worked with, the number of people supervised, and the budgets you've managed. Use short phrases and keywords. A good place to use bullets is to highlight achievements on the job.