Beware of folklore like "...you can tell if a snake is venomous by the shape of its head." Everybody has heard those cliches, but they are simply not true. Most snakes (venomous
and non-venomous) have triangular or spade-shaped heads.
If you encounter an Eastern Diamondback Rattlesnake, you will see a dramatically triangulated head, but there are at least two venomous American species which don't have triangulated heads. The coral snake (our most deadly snake) does not have a triangular head at all. The pygmy rattlesnake (quite common in Florida) has a little triangulation to its head, but the snake is so small that you would probably not describe it as triangular.
It is far easier to identify a snake from a picture in a book than it is in real life, so the sensible thing to do is to stay away from them. You don't have to run from snakes; if you stay the length of its body away from any snake, you can watch it all day if you want without any danger.
Teasing snakes, as described in an earlier post, is just plain stupid. If the teaser were an adult, I wouldn't interfere with natural selection.
