When i started to play NLHE, my friend told me that a very fast and pretty accurate way to calculate my % of hitting a hand on the next card was to calculate my # of outs, multiply it by two, and then add one.

When i read a lot of articles for beginners, I don't see it done this way. Whenever I watch the TV shows where they show the percentages, the way I learned it is actually pretty accurate

Should i stick with this method? It's good for me because I can calculate a % real quick, but perhaps I am missing a faster or more accurate way of doing it