Back in the early days of human flight, people would strap a set of wings to their backs, run towards a cliff and jump. Rather than swooping into a graceful flight, this would generally result in a painful crash. But if they had tried this on Titan, one of the moons of Saturn, they might have actually been able to fly.
Titan has a very dense atmosphere, denser than that on earth and a much lower gravity (0.14g compared to Earth's 1g). All this means that an average adult, wearing a wingsuit with a decent enough wingspan could get enough lift to fly.
Having said that, our would-be pilot would need some equipment to survive the flight. First a set of oxygen tanks and a respirator, because breathing the air on Titan would kill us (it contains mostly nitrogen and some methane and hydrogen, but no oxygen). Also, some warm clothes would be needed. Titan's average surface temparature is about -179 °C. Lastly, flyers should prepare for rainfalls of methane.
Other than that, you would totally be able to fly on Titan.