When your good position fails you.

Honestly I've played many a game where I would ruin a good position simply for my lack of ability to take advantage of it. I can have 3 pawns in the center without my opponent even considering a strike at it until move 20 and I wouldn't get the win. In fact, my saying "A pawn up but a game down" is becoming terribly true sometimes.I find plans like anyone else, so I don't think I'm terribly bad at strategy,but I highly doubt that good positional chess is all about 'lookin pretty' with your nice position. I find myself in losing positions very magically, even when my opponent misplays the opening with early queen development and such. I really want a few suggestions if you guys wouldn't mind it.

Thank you for your help but I'm talking about strategically lost positions, not positions where I oversee tatics.I bought daniel naroditsky's mastering positional chess and unfortunately the ideas he displays in that book are a far cry from what I can think in my own game.

It could be that you know what a strategic advantage, like a central pawn majority or better pawn structure looks like.   But don't know how to exploit it.  It is consistent with what you say.

If that is so, you could go back to the strategy guide with this in mind.  And find model games where a GM has exploited that kind of strategy.

The answer: 

If you have a strategically won position, the only way (well, the main way) to lose it is to miss tactics.

Either winning tactical ideas for yourself, or saving tactical ideas for the opponent.

Anyway, a common misconception for lower rated players is thinking a few minor opening mistakes will lose the game. You have to play exceptionally well (like GM level) to convert opening inaccuracies into a win. So my main advice for you would be to not underestimate your opponent's position.

ПРЫХ СКОК МУХА МУХА АА ПРЫХ СКОК МУМУХА

ПРЫХ СКОК МУХА МУХА АА ПРЫХ СКОК МУМУХА

just pick the best moves continuously.