The right equipment.

Although technically there are no real equipment requirements for parkour, there are some guidelines that will help you pick what to wear depending on your skill level and your planned parkour environment.

Headwear

In colder climates, the classic beanie is a must have. You should look for a beanie with fairly good insulation, and with the right fit. Before buying, make sure that the beanie is not too small, otherwise you will feel discomfort. Also, if the beanie is too large for your head, it may slip off during high velocity movements.
In hotter climates, try the faithful cap. Caps not only provide sun protection, they can also hold back longer hair out of your face, a valuable safety asset. Be careful with caps in windy places, as the brim tends to pick up air and try to lift the cap off your head. Check for a snug fit, or go for a cap with a resizable back strap. This will ensure that wind won't cause too much trouble and that your cap won't fall off during flips and high velocity movements.

Footwear

Shoes should have a sturdy, durable sole and should be light enough to make distance jumps. You should always check for a snug, comfortable fit. You may spend up to 6 hours on your feet during a session, so make sure your shoes don't cause blistering or restrict circulation.
Most running shoes are suitable, make sure they grip well and that the sole is not too floppy. Skate shoes are usually very lose, which may lead to injury. Skate shoes are designed for skating, they don't have the same shock protection as other types of shoes.
Choose a shoe that is suitable for you, have it professionally fitted if need be. Look for a good fit and suitability for your arch, cushioning on the rear and front of the foot and any motion control you may require.
Thicker socks may provide slightly better shock protection. Make sure they breathe otherwise you will come home with a horrible stench in your shoes.

Gloves

Gloves may provide protection from cuts and scrapes during intense drilling. Half-finger gloves are the gloves of choice, they let the skin surface provide fingertip grip on obstacles. Gloves are mainly a training tool, good for beginning on rough surfaces, but ultimately you will have to abandon the use of gloves as you get more experienced and rely on yourself to prevent injury to your hands.

Wrist

Some people use sweatbands to protect their wrists/forearms from minor scratches and cuts that occur during climbing. A sweatband can be worn over a watch to protect it from scratches. Long sleeve clothing will provide some degree of protection against scratches.

Pants

The pants you wear will depend on the climate mainly. Tracksuit pants of pants made from lighter materials are the pants of choice. Make sure they are breathable. Your pants will get dirty during rolls, climbing etc. I do not recommend jeans as they are usually too heavy.
Make sure that you pants don't hinder movement by moving your knee to your chest at 90 degrees to your body, and then bringing your knee up up your side making your thigh almost parallel to the ground. If your pants stop you from doing this, find a new pair of pants.

Torso wear

I recommend a long sleeve garment for rolling practice or first time cat jumps. Eventually, you should be able to roll on most surfaces without protection. A bulky jacket or jumper will hinder movement of the arms and torso. A thinner breathable garment is preferred.

Storage devices

If you don't plan on doing high intensity moves or rolls and need to cary things around or move locations alot, a small backpack is the most practical portable storage you will find. Look for a backpack that has a fairly small profile, adjustable straps should be adjusted to fit the backpack close and firmly to your body. A bag with both chest and hip straps will provide the least discomfort when running.

Other protective gear

If you have special circumstances, such as pre-injured joints or recently healed fractures you may want to use protective gear to prevent serious re-injury.

So now you are geared up, take to the streets with some parkour action!

Hawken