There are many opinions about grooming.  I have read and studied and listened to the reasoning behind different choices and have come to my own conclusions and choices for my own dogs.  I encourage everyone to read about grooming on various breeders’ websites and find what makes the most sense to you. Our friends at Blizzardpeak go into great detail.   Having had long haired sheepdogs for 40 years before Bergamascos I have a strong desire to brush!!  Partially because it has been ingrained in me that an un-brushed dog has a bad owner.  (I had to get over that)  I did however, keep each of my girls brushed out until their matting was next to impossible to keep up with (about 18 months of age.)  Once I let it mat and flock I had fuzzy ends that later had to be cut off the ends of the flocks. (I know this isn’t the way everyone does it.) As the coat flocked I continued to keep head and neck and chest brushed.  This really does help with the smell.  Food doesn’t sit in the beard and the ears don’t have mats/flocks which also smell and are difficult to split because ears are tender and the skin is thin.  A tool I could never do without is this pricy comb:  I use it lengthwise to pick gently through mats I am separating.  Keeping the chest brushed helps my agility dog move freely and keeps the other two from being encumbered by too much weight.  This is a link to my favorite brush: I use the double sided dark blue for the larger areas and a single for they ears and head.  I also brush feet because stickers are easier to find and remove and dirt doesn’t stick as badly. 
Once the hair starts to mat it is important to begin to separate the mats.  Sometimes they form in a fan and only need to be pulled apart in one direction but other times they form one large sheet which is more difficult.  I usually try to pull apart the mats from the outside toward the skin but sometimes find it easier on the dog to use a mat knife and slip it under the mat at the skin and slide it outward, cutting the mat apart.  When you first begin the process of separating flocks it takes a lot of time. The mats keep growing back together and it seems like it will never end!  Once the flocks are formed they continually need to be pulled apart as they grow.  But that is like a dog massage in our house.  Cuddle on the couch and play with flocks.  Except for their ticklish legs the dogs all love the attention.
Some people take their dogs to a groomer.  I have never done that.  It is “hop in” at our house and into the bathtub they go, some more willingly than others!  A hose with a nozzle is pretty much essential with a Bergamasco.  I soak them down with water and watch the tub water darken!  Then with diluted (approximately 1 part shampoo to 3 parts water more or less) dog shampoo (I have used Mane and Tail, Buddy Wash, Traleigh any good pet shampoo will do) I pour it over the back and squish it into and through the flocks.  Be careful not to get water into their ears and try not to get it in mouth and eyes which is tough when you are trying to really clean a shaggy face.  It takes a while to really soap down a dirty Bergamasco and by that time the water in the tub should be really dark!!  Once they are soaped down then rinse, rinse, rinse!!!  And then rinse some more until the water runs clear!!!  After they are rinsed I mix white vinegar 1 part to 3 parts water and pour this mixture over the dog and squish it through the flocks.  It helps get the last of the shampoo out and keep the dog from smelling like mildew if the flocks take a while to dry.  After the vinegar and one more water rinse I dry the dog’s face and ears and eyes with a towel.  I squeeze the water out of flocks and then soak up more water with a towel and then another and maybe another!  When you think you are done there will be more water dripping out of the flocks!  You can also use a blaster which really helps to remove water from the flocks.  But blasters are noisy and some dogs don’t tolerate loud noise.  Some people have elaborate crate drying systems which I envy!  I try to pick a hot dry day or better yet a hot dry windy day and let nature help!  (dogs in ex-pens on the deck in the sun) Or if it is winter I put an ex-pen up in front of the fireplace with an additional fan and on top of towels and change the towels often!