During WW2, Yugoslavia was attacked by the axis and relentlessly carved between various axis-aligned states. However, not all of the yugoslav populace was chummy with the axis occuptaion, and formed a resistance movement collectively known as the yugoslav partisans. For most of the war, the yugoslav partisans remained a harassment force, if still dedicated to liberating their country. Tito's socialist partisans eventually gained a good reputation and were admitted as the official government of post-war Yugoslavia after defeating the axis puppet states in the region.
So, how do we make the Yugoslav partisans more successful than OTL, up to the point of occupying enough of Yugoslavia to harass Italy? Above all, how do we make them successful enough for them to receive territorial concessions as spoils of war, especially the territory of Friuli?
To which yugoslav state would Friuli be awarded, or would it be admitted as an independent ethnic italian state? If the former option is used, would an expulsion of the italians be needed in the territory, like how the germans were expulsed from their former eastern territories?