If your car's in need of a little tender love & care, check out Mr. Tire's free tire rotation & inspection offer, along with a few other checks. They'll probably try and upsell extra services to you, but you can simply say no and get the free tire rotation. They also have a coupon for a free flat tire repair
This reminds me of my super-broke college days. In addition to changing my own oil, I tried rotating my tires and got bored / tired / distracted halfway through. Took me about three weeks of walking around everywhere to finally go back and finish the job.