Even if you're not ready to sell your earthly possessions and hunt squirrels with a handax, there are many ways to add some wild into your otherwise tame existence. You could start by taking more hikes in forests, coastal trails and other pristine natural settings. Pay attention to the animal and plant species you encounter and appreciate the diversity and complexity of the natural world.
If you want to take your rewilding experience a step further, consider taking a class in one of the "primitive arts" like foraging, bow and arrow making, toolmaking, or wilderness survival. Search online for classes or programs near you by Googling "wilderness survival classes" or "survival skills" along with the name of the closest city. If you live in the Portland area, look no further than Rewild Portland.
Some programs also stress the philosophical component of rewilding. For instance, ReWild University's website says, "Instead of leaving with only a set of skills, you'll come away having opened a gateway into your ancestral birthright. What is this birthright? A mindset that is stress-free and aware. An every-moment sense of adventure. A body that is characterized by vital health. And most importantly, you'll gain an understanding of how to integrate your rewilded lifestyle into your everyday life."
If you really want to know what it feels like to live like Paleolithic hunter-gatherer — at least for a few days — consider taking a "survivacation" at one of many wilderness retreats around the world. Celebrity survivalist Creek Stewart coined the term "survivacation" for his three-day survival skills retreats at his Will Haven Outdoor school in Indiana, but you can find similar short-term retreats as far away as Australia (it's called "bush survival" down under) and Sweden (in winter!). You can even be stranded on a desert island in Indonesia [source: Lin]. For serious students, Earthwalk Northwest offers a year-long apprenticeship program in "Primitive Living Skills."