I have organized Diplomacy for new players at my home twice, and it was a success both times.
I would recommend you to not play yourself. Not only is it more fun when all the players are roughly equally experienced, you also will be available for players to ask questions to about how certain moves would be adjudicated. Plus, it is incredibly fun to overhear new players in tense negotiations.
I started off by first explaining the rules of the game to the players in roughly 30 minutes, and then starting the game. I used a timer to keep track of how far we were in each phase, and I gave the players the appropriate amount of time, though the timer was paused during all the adjudications. Every time when time was almost up, I would notify the players who where spread through my house. In my experience, the players will start feeling the time pressure during the second year, because then they will have more units.
Multiple rooms in my house were assigned 'negotiation rooms' where players could negotiate, and all of these rooms had a miniature version of the board printed on paper to help the players. At some point the players started making pictures of the board though, which I can recommend because that indeed helps them.