Back Yard Permaculture
You may feel, like I did at first, that there is no way to engage in permaculture if the only land you have is the small plot around your house, or a miniature yard behind your apartment. However permaculture principles can be applied to any area, no matter how small.
First, think of whatever space you have as a system. Examine the pattern of the community in which you live and consider how you can fit into or improve it. Pick up coffee grounds from your local coffee shop. Work with your neighbors to plan the location of shade trees so that they are appropriate for everyone who will be shaded. Consider ways to use solar energy.
Strive to make the system as closed as possible. Compost kitchen waste; make a greywater use system if possible. If rerouting piping is not possible you can catch the water in a bucket as the shower is warming up, or wash vegetables in a pan in your sink then dump that in the garden. Leave tree leaves on the ground to decompose where they fall or put them in a wire cage to make leaf mold over the winter.
As you plan your yard, consider the needs of everyone in and around the house. Children need a place to get out and play. Adults need a place to experience natural beauty. Rainwater should be allowed to soak in, not channeled away as quickly as possible. At the same time you need to consider how to protect yourself as well as your neighbors from mudslides originating in your back yard. Be open to new ways of thinking about your yard.
Every yard can produce something, if only some tomatoes from a large pot on the balcony. Strive for a combination of beauty and food production. More diverse plantings not only provide more interest in the landscape but make a healthier environment. Fill that yard with as many locally adaptable varieties as will fit comfortably.
If possible, add some animals to the mix. Bees, rabbits, chickens, pigs or goats can be contributors to the human food chain, while more traditional urban animals like dogs and cats can add a bit of manure to the system if handled properly. Make sure you meet all animal welfare and sanitation policies of you area.
By gradually making changes to the yard you have now, you can create a little bit of permaculture in your own back yard.