Make sure EVERYONE knows that Italy is the weakest country, by reminding them of it constantly, both during the game and every time the subject of Diplomacy comes up in conversation generally.
Hopefully this will lull them into a false sense of security, so that you can actually get somewhere with your beleaguered green armies.
Certainly if anyone starts picking on you, you are entitled to complain loudly:
"C'mon!
Everyone knows that Italy doesn't stand a chance of winning this game!
Stop hassling me!"
Of course, this meta-strategy can easily backfire: if you become just too annoying and whiny, people may start attacking you just in the hope of shutting you up!
But generally I think it's perfectly reasonable, given the common knowledge that Italy is far from the strongest position in the game, to present yourself as an underdog and no real threat... until you've rallied your forces sufficiently to strike.
It's all part of the fun of the game!
boardgames.stackexchange.com/users/436/thesunneversets
The Diplomacy Archive has a large number of strategies for Italy and all the other countries .
It also has some articles by Allan B. Calhamer (the inventor of Diplomacy).
boardgames.stackexchange.com/users/73/Jon Hadley
You absolutely need to have some dirt on Austria; it will be very difficult for Italy to do well in the face of a hostile Austria.
Even if you join a coalition against Austria early on, you'll find that most of the SCs wind up falling into Turkish hands, rather than yours, leaving you with little better in the way of options.
boardgames.stackexchange.com/users/71/GWLlosa
I'm a big fan of the Lepanto opening: Spring 1901:
Rom - Nap, Nap - IonFall 1901:
Nap - Ion - TunBuild F NapSpring 1902:
Ion - Eme, Nap - Ion Setting up a fall 1902 convoy into the heart of Turkey.
The main weakness is that this leaves your defenses entirely the responsibility of your northern army, and so requires that you use diplomacy to keep your neighbors from attacking you.
boardgames.stackexchange.com/users/55/Simon Withers
One winning strategy is to make an early alliance, preferably with Austria and then knock out Turkey and turn on France.
You'll probably have to backstab Austria at some point -
certainly, I've never got to 18 without Trieste - but
that's the usual backstab timing question.
boardgames.stackexchange.com/users/49/Richard Gadsden
Don't worry about "backstabbing" Austria.
Try to follow the real life World War
I strategy of making peace with France, and ally with Russia against Austria and Turkey.
If necessary, let Turkey in the initial alliance against Austria, then convince Russia to side with you against Turkey, who would otherwise be stronger than Russia.
Trieste is HUGE for Italy.
You will have a line of four connected supply centers (Naples, Rome, Venice, Trieste).
Five, if you say that Tunis is "connected" by sea with the others (I'd call it 4 1/2).
If France won't make peace and Austria will, ally with England and/or Germany against France.
Hopefully, you'll end up with Marseilles and Spain.
But they aren't connect to homeland supply bases like Trieste, Serbia, etc. would be.
The other problem is that while Russia is a natural ally with you against Turkey, she isn't against England.
boardgames.stackexchange.com/users/1344/Tom Au
I am a big proponent of playing as Italy.
Here's how I do it: no diplomacy for the first year!
A
Ven - Pied & A Rome - Ven! Attack Marseilles and Trieste!
(also grab Tunis)
If you get both SC's, try to ally with Eng/Germ/Russ.
If you fail to get allies, promise to vacate one and focus on the other.
It is easier to ally with Austria than France in my opinion at this point, because it is harder for Austria to not care and attack you all out.
France can swing south and make it hurt.
Ideally, you want to get a Fleet in to the English Channel by 1904!
This way you own the EAST.
Do not ally with Turkey unless he becomes a land power, because his fleets are dangerous.
Good luck!
boardgames.stackexchange.com/users/11656/aaron
Italy is almost the worst country to start with. But that makes it a nice challenge.   What is your winning strategy with Italy?
What is a winning strategy for Italy with Diplomacy
boardgames.stackexchange.com
<diplomacy>
boardgames.stackexchange.com/questions/11
boardgames.stackexchange.com/users/45/Toon Krijthe
Let Turkey be in the initial alliance with Austria, then convince Russia to side with you against Turkey. Do not ally with Turkey. The Diplomacy Archive has a large number of strategies for Italy  and all  the other countries. One suggestion is to play as Italy. It might be easier to ally with Austria than France, because it is harder for Austria to attack you all out. You could let Turkey in the initial alliance against Austria, then convince Russia to side with you against Turkey. Do not ally with Turkey unless it becomes a land power, because its fleets are dangerous.
The Diplomacy Archive has a large number of strategies for Italy  and all  the other countries .    If necessary, let Turkey in the initial alliance against Austria, then convince Russia to side with you against Turkey.  I am a big proponent of playing as Italy.  It is easier to ally with Austria than France in my opinion at this point, because it is harder for Austria to attack you all out.   Do not ally with Turkey unless it becomes a land power, because its fleets are dangerous.