What can I do to increase the size of my masseter muscles?

I want my jaw to be similar to the actor James Hyde, and although my jaw is similar in size my masseters aren't as large as his, I don't want plastic surgery since I plan on fighting and I don't feel right about inserting foreign objects into my body. I know that my body fat is higher than his, but even with losing weight my jaw wouldn't be as wide and as square. Is there any way I could increase the size of my masseter muscles/expand the width of my mandible? What can I do to achieve this look?