The principle causes of diarrhea, especially when transitioning a dog to a raw diet are: introducing organ meat too quickly, too much fat introduced too quickly, too much variety introduced too quickly, and overfeeding.
Avoid these potential problems, and you'll be good to go. Diarrhea is not normal--and I'm now on my 6th raw fed dog (all but one started as weeks-old pups) and never had a single one transition to raw with problems.
The first raw meals should be simple, single ingredient meals. Good thing the chicken worked out for your dog, because that makes it easy.
Start with chicken backs. They are the perfect dog food. You will want to peel off the skin and any visible fat for the first several meals. For muscle meat, use boneless, skinless chicken (i.e. thigh meat or breast.)
The ratio of backs to boneless meat should be about half and half by weight. Feed nothing else but this skinless chicken for several small meals--until you see the dog producing firm (but not hard or crumbly) log-shaped poops.
This poop fixation will be a thing for a while.
Once you see several good poops, start adding in a small amount of the chicken skin to the meal. Wait for good poop.
Once you are able to feed the chicken with all the skin, and still have good poop, then you are ready to add in one new ingredient. I'd keep the chicken back and use a red meat for the muscle meat--a small piece of pork or beef. Then poop test.
Once you've passed this milestone, you can start to think about adding a tiny piece of organ meat--like chicken liver. But make it tiny. Like the size of your thumbnail. Too much liver at once for a dog unused to it WILL CAUSE DIARRHEA. Organ meat is a very important part of the diet, and you'll eventually want to work up to about 10% of the meal's weight in organ (liver, kidney, etc.) But do it gradually.
You'll continue in this add-one-thing, watch the poop, for as long as it takes. Better safe than sorry.
Variety is important. But not all at once. Over the course of several weeks, you'll be able to introduce one new source of protein at a time, until eventually, you'll be offering the dog a wide assortment of proteins. Not all in the same meal, necessarily, but aim for several different protein sources fed over time.
Meal size is important too. Start with perhaps three small meals at first. Once things are going well, you can then transition to two meals a day. Some people only feed a single meal---but I've always fed 2 a day for my dogs.
The amount of food should be approximately 2% of the dog's ideal ADULT weight in food per day (divided by however many meals you're feeding.) Buy a scale and weigh the food. It will make it much easier for you to know if you've got the right ratio of RMB to MM to OM--and the right meal size. You may eventually get the point that you can eyeball a precise meal, but not to start with.
Should you want to add in small amounts of plant foods (greens, berries, low-GI starches) these should also be introduced gradually, and are not necessary at first--but I think they are a good way to add additional nutrients and variety. Aim for less than 10% of the raw diet in these non-animal sources.
Hope some of this rambling helps. Keep asking questions.
Cinco | Jack | Fanny | Ellie | Chip | Deacon