I need to improve my braking skill till I will be able to make a fast stop while travelling at a medium-high pace. I need it to ride my uni with my wife and my children using bikes in crowded bike paths.
So I wish we could build a manual of exercise to develop a unicyclist braking ability.
You should check out this thread:
http://www.unicyclist.com/forums/showthread.php?t=114830
Someone mentioned here - or maybe on the french forum - that the best way is to wear all the protections you own, including a padded backpack. Then you pick a place ideally with tarmac leading into grass. You go for it, riding hard, and a little before the grass part you let yourself fall backward. Then you use the brake to bring yourself back up. You will fall, several times, and on your back. But you have protection and grass for landing, so all fine. You’ll get the hang of it pretty fast.
I have yet to do it…
Funny, don’t you look forward to falling backwards on ur arse 
Just like learning to ride a freewheel. I do hope to one time find the time again to practice things more. Now with a young kid in my life that needs a lot of attention, I only manage to ride once a week, and then prefer to ride at least 20km instead of practicing tricks. I do try some hops along the way.
Being able to brake abruptly seems like a nice skill to have.
Why do I have pictured in my mind myself not falling backwards but rather leaning way back, grabbing a handful of brake at the edge of pavement and being catapulted over the top across the grass? Guess I know my limitations.
I would not use during static hopping, maybe a bit for petal position on downhill rolling hops, but generally not.
They are useful when mounting on a steep downhill.
Don’t do exercises that make you scared of the brake. Start with gentle use with light pressure and work your way up to more intensive use.
No reason to use a brake for hops, unless it’s when landing drops on a steep landing. But I would consider that a pretty advanced technique (but not as scary as most people here probably think).
To learn how to use the brake, I recommend gently pulling it on a nice downhill (smooth terrain). Try and get a feel for how much you need to lean back to compensate for the braking, while having the brake engaged at one constant point. Do that a lot, until you are not surprised by the effects of the brake anymore.
Now, play around with the brake on those downhills, to find out what happens when you pull it harder/open it up. You can try and figure out how to use it to slow down your pace, and how to open it up and go faster.
Once you are comfortable with modulating your speed with the brake, try and use it to get to a full stop. Don’t try to stop a 36" at full speed on a dime, just use it to slow down instead of your legs, and after a while, it will feel natural and enable you to slow down faster than you could with just your legs.
You will likely experience a few falls during practice, and that’s perfectly normal. The brake isn’t as much of a mystery as people think on here. You just need to learn brake feel. Basically your finger needs to learn when to pull harder, and when to open the brake up, while your body needs to learn how to anticipate the effects of pulling the brake. (You can’t really isolate those parts however during normal riding).
I cannot make scaring exercises! I train during work lunchtime break everyday. I cannot enter office with scars or bleeding… so I wear all protective gears that exist (heard a woman saying… “Are you heavy armored because of a war?”) and don’t try difficult stuff…even if I
make a superman flight twice a month.
So I’ll start with gentle brake exercise
I’m still not 100% comfortable with my brake, I think living without one for so long has burnt in some strong habits so when I do use it I tend to over-compensate with my legs and go flying 
Did an exceptionally hilly ride a few weeks ago though and made pretty good use of it. I started holding the brake before I hit the hill, so I was sort of pushing against it with my pedals, then once I was going down the hill it just felt a little smoother. I still can’t stop dead with it though.
What wheelsize are you using? Is a brake really necessary for dodging walking zombies and dogs on a shared use path?
Keep going
Wow - 20k? That’s pretty awesome dude. Let us know when you introduce your kid to unicycling. Let’s see if he can continue the tradition
With the 29er I cannot make a sudden stop (less than 2 metres) unless going slow (I’ve set the saddle with the nose down an I’m always falling in front: I’m training at fast riding)
With the fixed G26+ (this month will make first attemp to have it pedal assisted!) it is impossible to brake quickly using only legs!
If your pads are black, you can pretend it’s Batman vs. Superman. 
(In any other movie they would figure out how to have a conversation instead of fighting – and Batman wouldn’t have a chance)
As with a car, usually the best way to avoid a collision is not by braking, but turning. Even with a big wheel, if you practice for it, you can change direction very quickly.
That’s actually very good advice. Its prolly easier than an abrupr brake and staying on. When riding with some unicyclists some months ago, I needed to make some abrupt halts, which meant jumping off because the guy in front of me UPD’d. Maybe with a sharp turn I can keep going next time.
A unicycle will never be able to do a bicycle-style panic stop - physics is against us.
On a bike, my center of gravity is well behind the front wheel, and I can instantly grab the brake hard while sliding my weight even farther back.
On a unicycle I start with my center of gravity directly over the wheel, and I literally can’t brake - I have to get the wheel in front of me before I can begin. I have to speed up to slow down! And on a big wheel, with short cranks, it’s going to take a while.
However I must learn. I did 12km runners’ race today. I dribbled a lot of runners but we were about 200 people on a narrow path and 4 steep down and uphill… I cannot idle, nor ride too much slow. I must master unicycle brake skill
A brake will help you slow down, but not ride slow. Riding slow is a different skill.
I’m thinking you have that wrong - better to learn to ride slow (and maybe also idle) than to try and compensate for not having that skill using a brake.
I always stop myself when I notice I keep pedalling faster and faster, because I think when you can ride slowly it proves you control the uni. Motion is needed for balance of course and riding faster removes the side balance a lot, like on a bike. When riding in the forest I adjust the speed when needing to pass peds and when there is oncoming traffic. Though I would hopelessly fail at slow-ride uni competitions, I can ride slowly enough to find the time to pass the pedestrians.
I’m learning to ride slow, but braking fast is a skill I cannot forget. Here’s a picture of me Saturday riding really slow among pedestrians… the boy on the left crossed quickly the path without watching, nor listening me say loudly: " I’ll pass at your right side, please watch out!" I squeezed the brake lever and grab firmly the railing in the path’s side. Nothing went wrong, but I more sure than ever that I cannot ride without brake mastering!
I’m sure this is not what you want to hear, but: You shouldn’t ride on a crowded sidewalk like that.
I’ll second finnspin on that. My skills riding slowly and in tight spaces have improved a lot in my 4+ years of riding, but so has the frequency of my dismounts around pedestrians. I got this advice from a John Foss post: When people see you walking your unicycle, they may be curious if you can ride it and how you are going to mount it. You are more likely to get in a conversation with a stranger about unicycling if you step off the unicycle, which is good for the sport. If you wish to stay on the unicycle because you struggle to mount, then spend extra time practicing mounting. If you’re trying to set personal records for distance sans dismount, that could result in some bad decision making around pedestrians.