How big are your forces, or games?
We don’t usually have a problem in an evening’s game. Often, it is quite obvious who has won. If you’re playing to a scenario, which we usually do, you should have objectives, but even if you aren’t playing to a scenario, set yourselves objectives or an objective. Once you have achieved them you could consider that the winning point. If it is uncertain and a chance your opponent could retrieve it, set a limit to how long you should hold it. Basically, if you achieve it when your turn is second, play another turn where you must hold it. If you went first, your opponent still has his/her turn to try to wrest it from you.
Alternatively, ignore the parameters set in the rulebook and make up your own. Say, first side to lose a set number of units and the game is over, if time is short. There are a number of variations on this that you can use. Just remember that the rules are yours to play around with and tweak to fit your style of play.
Hope that helps?
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