Both my guys have strong prey drives, and neither was good with cats, but I had 6 when I got them, so it wasn't a choice.
I started them out interacting with the cats on leash only, so I could keep complete control and make any necessary corrections. I didn't remove the leash until "go easy" and "leave it" were being followed consistently. Once I removed the leash, (weeks later), I kept the interaction brief, always ending on a positive note and by 'putting the cat away' somewhere safe away from the dog.
The hardest thing is when the cats run, because lets face it, cats are fun to chase. Mine all have claws, so that was extremely helpful, but again, commands such as "easy" or "leave it" are very valuable during the chasing game.
Many dogs will eventually learn that the cats are part of the family, and although they may play too rough with them and could hurt them---(so they should never be left alone together)---they will accept them as 'part of the family.'
Babygates, etc. help, because they can get use to one another without incident.