If you like the traditional look of leather and you live in a region where the temperature plummets once the sun goes down, perforated leather clothing can increase airflow during the day and provide warmth during chilly evening rides. But jackets and pants constructed from lightweight fabrics -- nylon is one of the most common materials -- with mesh linings underneath offer much more breathability for consistently dry, hot climates. These typically incorporate ventilation panels on the chest, back and arms to promote air flow, and many even have interior liners and insulation layers that can be removed or replaced to help regulate body temperature. Lightweight jackets typically incorporate extra foam padding on the shoulders, hips and other points of impact to protect the rider. To prevent this padding from coming loose during a collision, jackets and pants should have a snug, but comfortable fit.
Ventilation is an important feature in your riding apparel because it allows cooler air to circulate against the skin while allowing your heat to escape. Generally, waterproof winter boots have poor ventilation, so opt for warm-weather boots with mesh ventilation panels. Gloves should incorporate mesh or perforation holes on the top and leather on the palms for collision protection.
A base layer is essentially for keeping cool. These shirts and bottoms constructed from sweat-wicking synthetic fabrics draw the moisture away from the skin to the outer layer of the garment and increase the efficiency of sweat evaporation. Motorcycle-specific brands often augment these garments to fit a seated cyclist: For example, the sleeves and the back are elongated because of a cyclist's bent-over posture.
In dry climates, riders can choose cooling vests, which they soak in water and drape over their torso to keep their skin damp and cool.
Last, soak a scarf and wrap it around your neck. It will shield your neck from the sun and cool down the blood passing through the carotid arteries. Some scarves are made from synthetic fabrics that purport to absorb more water and keep you cooler for longer periods, but a standard cloth bandana can work in a pinch. Soak the scarf in water and re-wet it as needed. While you're at it, take off your helmet and soak your hair to cool down even more.