If you're using
DCL transportation, getting to the port and onto the ship is really easy. When you check in at the hotel, they will give you a letter (or provide one to you later in the day) with instructions on what to do. There may be a DCL rep at the hotel depending on what time of day you arrive. The letter will tell you what to do with your luggage, where to meet the transportation, etc. When we took DCL transportation in London, we had to sign up for a time to go over to the port - they had transportation leaving every 15-30 minutes. The luggage went over in a separate vehicle.
We stayed at a DCL hotel in Vancouver and while we could walk to the port, we had DCL take our luggage from the hotel to the port for us so we didn't have to drag suitcases across the street. That situation was very similar in that we got a letter with instructions for what to do - for having our luggage ready for pick-up by a certain time, etc. And there will definitely be a DCL rep that morning, so you can always go for a quick chat / check that all is well.
So then they transport you over to the port terminal and from there, it's much the same as anything else - have your cruise documents and identification ready and you'll check-in there. Sometimes they have check-in at the hotels so you can do everything at the hotel with the DCL rep including having your pictures made so when you get to the port, you don't have to do all that - they will tell you what to do and when to do it.
Then you get on the ship and after that, it's the same as every other cruise!