One way to minimize the number of things you have to buy is to get the most out of what you already own, and one way to ensure your things get high mileage is to pick up the tricks for repairing them.
The Natural Resources Defense Council's journal, This Green Life, just released a helpful guide to becoming a repairperson for your own things. Included in the guide are shopping tips for finding durable goods, information on making repairs to a variety of products, and advice for how to decide whether to repair or replace. iFixit is one of the resources the journal article shares. It provides free manuals for repairing many different things.
I get excited about ideas like this because they focus on sustainability, help make the old new, and empower people. Empowerment against consumerism is a difficult thing to achieve, but this is a good start.
In the near future, I will begin a project to rejuvenate my computer. I bought it as a refurbished model, and it is now more than four years old. Rather than get a new computer, I'd like to see how far I can go with this one, so I will be replacing the hard drive and updating the operating system. Hopefully, that will keep it kicking for a few more years. I'll have more about the project later as an example of getting the most out of products.