You will get a warning message when you reach that point of no return. The warning is unmissable: it appears at the center of the screen, and the gameplay pauses until you make a decision.
It's not necessarily about moments of no going back, but more so based on how long you can work with a faction until they demand hostile action towards another. Sometimes, a warning for this will appear, other times without a warning.
These are the quests for each faction that will make another hostile towards you:
For the Brotherhood of Steel:
Spoils of War will turn the Institute hostile (NOTE: This quest is intertwined with Mass Fusion).
Tactical Thinking will turn the Railroad hostile (NOTE: I believe activation of this quest WILL turn the Railroad hostile automatically, keep that in mind).
For the Institute:
Mass Fusion will turn the Brotherhood hostile (NOTE: This quest is intertwined with Spoils of War).
End of the Line will turn the Railroad hostile.
For the Railroad:
Precipice of War will turn the Brotherhood hostile.
Nuclear Option will turn the Institute hostile.
Nothing can turn the Minutemen against you, although I do not know their specific quests that require hostile actions towards other factions. But who cares about the Minutemen anyway.
Be aware though, there are a number of ways to make a faction hostile during quests before these ones. But the quests I named are ones where it demands absolute hostility and there is no way around it (besides avoiding the quests).