Cycling: Top 5 points for Bike Safety, Braking, Descending / Cornering and Climbing.
Bike Safety Check: Top 5
Before your ride perform the following:
Check your brakes for wear.
Wheels: Check your quick releases (or through-axles) are tight. And your wheels are true.
Check your tires for wear and make sure they are inflated to the recommended pressure (this is found on the sidewall of the tire).
Clean and lube the chain
Check to make sure the bottom bracket / headset are tight and not loose.
Resources:
How To Check Your Bike Before You Ride - Pre-Ride And Weekly Checks

BRAKING: Top 5
Don't grab the brakes. Instead, feather the brakes by applying brake pressure slowly and gradually.
Anticipate when you will need to slow down and brake before hand.
Sit-up to be less aerodynamic and use your body like a sail to slow you down.
Front brake has more stopping power than your rear, however, both brakes together have maximum effect. The forces you apply may be different. For increasing your stopping use more force on the front brake.
Stopping fast: in a hard brake straighten your arms and move your weight backwards.
Resources: How To Brake Like A Pro - Road Cycling
How To Improve Your Braking
How To Perfect Your Braking

Descending / Cornering: Top 5
Practice leaning the bike to turn rather than turning the handle bars. Practice riding ‘S’ turns on a flat section of road. Focus on weighting your inside hand and outside leg.
Relax and lower your center of gravity (ride in the drops). This helps you be more stable and have more control.
Regulate your speed before a turn by feathering the brakes to scrub your speed. Try to refrain from braking once you’re in the turn. Braking effects are accentuated in corners. It increases the forces on the tires and is one of the biggest causes of crashes.
Eyes should be looking ahead beyond the turn / through the turn, and not down at the ground. You naturally ride where you look. Don’t look at the things you want to avoid! Looking ahead maximizes your reaction time.
Use all the road you have available to you. Smooth out the corners by cutting the apex of the corner. Ride from the outside of the