Braking seems pretty simple on the surface, but there's a lot to it, and you should practice.
Maybe you took the Motorcycle Safety Foundation class a million years ago and don’t remember much of it. Maybe your untrained buddy taught you to ride a bike. Maybe you listen to them when your friends tell you not to use the front brake because it will “send you right over the handlebars.” We are here to tell you: Your brakes are the most important system on your motorcycle and hard to master, but worth the practice. Mastering the use of your brakes can and will save your life.
I will posit here that most riders have no idea how fast their bikes can stop. Your motorcycle can stop really, really fast, but can you? Life isn’t perfect. The general car-driving public is not that smart, and someone, sometime, is going to do something dumb in your vicinity. It won’t be your fault, but avoiding them is your responsibility. Also, NO, your front brakes will not "send you over the handlebars" but offer your best hope for a quick stop. Most of your bike's braking force is in front.
Like your instructors taught you in your MSF class all those years ago, your braking should be progressive. That means that you squeeze, and do not grab, your brakes. Squeezing the front brake lever (and stepping on the rear brake pedal) slightly at first and then harder and harder the longer you have to brake, gives your motorcycle a chance to transfer weight to the front wheel and compress the suspension. All of that makes your braking much more effective. If your bike has ABS, you can practice your braking safely knowing that if you brake too hard, your ABS will save your bacon, and you and your bike will come to a stop without any drama.
The Important Part
Here’s the tricky part though, especially on forward-leaning sport bikes, but it’s very important: do all of your braking practice without bracing yourself on the bars. If you weight the bars you cannot turn them. Every motorcycle will handle better when the handlebars are free to turn. Squeeze the tank with your knees, and hold yourself up with your core. Try this, and then come back and tell me about what a revelation you have had!
Practice Practice Practice
In a protected area, practice coming to a complete stop as quickly as possible from faster and faster speeds. Pay attention to the feel of your brakes, and the noises your tires make in this situation. Soon you’ll be able to gauge your braking force by how your motorcycle is behaving, and even the howling noises your tires make. Keep your feet on the pegs until the bike is stopped, and do not neglect downshifting while braking.
Now Speed Back Up
Once you can come to a complete, controlled, quick stop, reliably and in first gear, practice slowing but not stopping. You’ve already come across situations in which you had to brake hard to avoid a collision but then needed to get the hell out of Dodge so that nobody hit you from behind, right? Slow the bike way down, then speed it right back up again. Pull that clutch in the entire time you’re braking hard, and tap the shifter with just enough of a pause to be in the proper gear for rapid accelleration at any moment. You will get good at the downshift timing. You’ll be able do slow down and speed up like a pro. If you get good at this "touch-and-go" technique, it can reliably get you out of hairy situations. It's a great skill to have in your skill tool kit.
You will discover that your bike can brake quite hard without losing traction on a clean, dry surface. This will give you the confidence to use all of your brakes’ capabilities the moment you really need them. Once you have the muscle memory of using your brakes hard and effectively you’ll be able to do it in a panic situation safely.
The best way to get good at something is to practice, and that means making the time and getting out there and doing things consciously and with awareness, regularly. Empty parking lots are your friends, but one day isn’t going to make you an expert. Grab some time to practice whenever you can so that your skills are there and aren’t dusty when you need them.
Further, read some great books on riding like Nick Ienatch’s Sport Riding Techniques and David Hough’s Proficient Motorcycling and then get out on your bike and consciously practice everything I've said here along with the things they tell you.