My cats have all gotten along with my dogs just fine. The DOGS are the ones that have to watch out!
The key is for the cat to stand its ground. If it runs, the dog will chase it, so have the dog on a leash. I would also make sure the cat has a safe place to retreat to - either under the furniture, or up high somewhere.
Tell the dog 'no!' if it tries to chase the cat, and snap the leash to get his attention off it.
My first time introducing a cat and a dog, I forgot the dog didn't have a collar on. So, when he chased the cat, there was NOTHING to hold on to! He actually grabbed the cat twice in his jaws before I was able to get in his way.
The cat wound up clinging to the Venetian blinds in the living room, but was unharmed.
Within a couple of weeks, they were playing together, and eventually sharing the same bed. I just made it really really clear to the dog that chasing the cat was NOT going to happen.
With my current cat, he just stood his ground, and if the dogs got out of line, he swatted them on the nose
Here's a photo of his introduction to one of my German shepherds.