If you are going to arrive in Antigua by cruise ship and want to make your own way to the famous Nelson's Boatyard then this is what you should do.
Exit the port and walk directly ahead as far as Market Street. Turn right along Market Street and when you get to the fork in the road bear right into Valley Road. The bus station is on the right. Look for the bus sign for Nelson's Dockyard or better still ask someone which bus it is. They're all minibuses. The bus doesn't leave till all the seats are full so you could be in for quite a wait but its great for people watching, The fare is about one and a half dollars each, each way and its about a 45 minute journey. Try and have near enough the right money as change is often given in Eastern Caribbean dollars. Nelson's Dockyard is the end of the line so you'll know when to get off. Obviously the return journey is the reverse of this. Cheaper than taking the ship's trip there and perfectly safe.