With a POD no earlier than the establishment of the Provisional Government on March 15th, 1917, have Russia emerge from the Revolution with some form of stable democratic or semi-Democratic government. I guess it helps if Lenin gets sick and dies on the train ride back to Russia.
You need a democratic body to oversee the Gosplan.
The Soviet Union already had, well, Soviets. The problem that undermined the collective enterprises was rooted in the administrative body that was responsible for the allocation of resources; a feature that is a must in a system that has done away with the market.
It'll be difficult, but possible.
Honestly, it might help if they keep the collectivization of enterprises but institute market reforms upon which said enterprises operate. Just let the market do its wonders at creating wealth whilst gradually subsuming the market with a planned method of distribution. You have to get rid of the Five-Year-Plans, because they destroyed any semblance of workers democratically controlling the collective. When you have a body that requires that x be produced in y time, the workers have no say in the allocation of the surplus-value.
So, I guess the only way is to to use a market system. Workers own and operate the means of production, but in a system whereby resources are allocated by way of supply an demand. Workers can choose, democratically, how to invest the surplus value in their respective enterprises.
That isn't to say everything would be distributed by way of a market based system. You'd need a central authority, obviously democratic, that distributes social services, like healthcare and education, by need.
So yeah, that's my two cents.