What makes your endgames

Probably the most helpful answer would break it down into different types of endgames, but the list would go on and on and more than a post it would become a small book.

e.g. You could start with king and pawn endgames, then R vs R , R vs R with pawns on one side, R vs R with many pawns, then do the same for RR vs RR and then start over with bishops, knights, queens.  Add B vs N then add unbalanced ones like RR vs Q, R vs B, R vs N, etc.  In each of these there are slightly different considerations, ways to win and ways to draw. 

Maybe if you narrowed it to a certain type of endgame someone would venture an answer.

I agree with the above, there are too many types of endgames to explain what makes one in your favor or not. But I think one universal endgame principle is, in an equal endgame position, whoever gets their king to the center and into the fight first wins.

I suggest you get an endgame book. I just started reading Silman's Complete Endgame Course, and I would recommend it. It puts all the endgame principles into an easy to learn ideas, and the material is broken up into ratings categories.

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