How do you crack an egg?
Crack sharply on a hard flat surface, and pull the halves apart on the break.
Use a flat surface so you don't shove shell bits into the albumen. When you pull, don't shove your fingers into the crack for the same reason. Most of the skill is in knowing how hard to hit the egg to get a crack without shattering the shell. Once you get really good, you can do it one-handed: hold egg in palm, smack on surface, and use your thumb and fingers to push it in half. It takes some practice.
I'm still undecided on the flat surface vs. an edge for breaking the eggs. The argument against using an edge is that you risk driving a chip of eggshell into the middle of the egg, but I find that a clean break is more significant for me, as anything less means that I have trouble separating the two halves, and end up knocking loose little bits of shell into my dish that I then have to go and fish out.
I will say that although I learned using the edge of a bowl, these days I use the edge of my counter -- it's straight, so I find it gives me a cleaner break ... just don't forget to clean and disinfect your counters afterwards. (I guess I could use a rectangular pyrex or similar container, too, but I don't know if the 90 degree angle vs. the edge of container would make a difference).
Crack on the lip of a bowl. You may need to practice a bit to get the exact strength needed, too much and it you break the egg completely dumping it into the bowl and on the table, too little and you need to try again.
Once cracked a bit, then pull two halves apart with your two thumbs.
Gently empty egg into your container.