Cutting, serving and eating a mango isn't as difficult as you might think.
The fun way:
Stand the mango up on it's end (you might want to slice a portion off the end so it stands flat)
Slice mango from top to bottom, parallel with the pit and as close to it as possible. You will end up with a large slice of mango with the skin still on. This is good and exactly what you want!
Rotate the mango and cut the other side the same way.
Cut one of the large slices into a grid pattern, through the fruit but NOT through the skin. Repeat with second slice.
Turn the fruit inside out, you will now have cubes of mango to eat straight off the skin.
The fruit that is still attached to the pit can be (carefully) cut off and eaten. Some people eat the skin, which is fine, but be careful of an allergic reaction, as it can happen in certain cases (ha, I sound like a drug company!)
The other, less fun, version:
Peel the mango with a vegetable peeler
Cut to remove from pit the same way as above
Cut into cubes or slices and serve on a plate or bowl
Told you it was less fun, but works if you want to add mango to a fruit salad or pack as a snack. Sprinkle with a bit of lime juice to further enhance the flavour.