Blue Mesa Trail

The easiest route is to drive from the southern entrance to the Petrified Forest National Park and head north toward the 3.5 mile Blue Mesa Scenic Drive.  The drive itself is nice and offers other hikes depending on what pullout you stop your car.  For the Blue Mesa Trail look for the 3rd or 4th pullout - the one with the covered picnic table.  

The hike itself is easy and flat.  You'll notice a steep decline in the beginning (meaning a steep incline at the end of the loop) but it certainly isn't intolerable.  The trail into the badlands is paved, so you could get by with sandals if that's all you have.  Even though the hike itself is short if you're going in the summer make sure you are wearing a hat and carry water.  You're completely exposed to the sun all throughout the Petrified Forest National Park.

If you're interested the Blue Forest Trail, one of their off the beaten path hikes (also in my profile) leads directly into and/or out of Blue Mesa Trail.

Don't forget to look around at all the different types of petrified wood throughout the area.  

From the Petrified Forest National Park website:  Descending from the mesa, this alternately paved
and gravel trail loop offers the unique experience of hiking among badland hills of bluish bentonite clay as well as petrified wood. Numerous plant and animal fossils have been found by paleontologists in the sedimentary layers of Blue Mesa.