I've been grooming for going on 12 years now, I've never shaved a dog while it's wet. No offense freedom, but I would not recommend that. I've tried shaving dogs that are damp still and it doesn't cut well I only do that to shorten the hair so it dries faster then I go back and shave it again when it's dry. With poodles and bichons you are supposed to blow dry the coat so it is no longer curly then cut the hair. At least that is how I've been taught? You DO need to wash the dog first, dirty hair does not cut well. I would wash twice (with dog shampoo, not just baking soda) and make sure the dog is very clean and fully dry before attempting this. Washing will make matts tighten and get worse so if possible brush the matts out before you wash the dog, if you can't get them out the dog will just have to be shaved shorter. What we do honestly is we do a "rough" cut and shave off the matts/shorten the coat, wash and dry the dog, then do a final cut. So if you have the patience I would do that, but if you don't have good clippers you won't be able to shave that long coat without it being clean either so that might not work. I also would highly not recommend using scissors, at least for most of the haircut. With inexperience and wiggly dog scissors can do a lot more damage than clippers. Believe me, I've seen a lot of home haircuts and I've seen some serious cuts done by owners with scissors. Yes you can injure the dog with clippers too but usually its more of a nick/razor burn not a deep gash. If your dog has more of a poodle coat you might be able to use cheaper clippers, if it has a thicker coat like a cocker I'd really recommend investing in a nice pair of clippers (nothing crazy, just like a basic andis 2-speed with detachable blades -around $100).