The first and foremost ingredient to choosing the right snake is the health of the animal. Once that is out the way, a number of other elements come into the equation. Species, age, temperament, colour, pattern, sex, feeding habits and price are all points to think about when looking for a snake.
If you are looking at a snake in a pet shop or other premises, do not look only at the snake. Look inside and outside of the cage for signs of dirty, unhygienic surroundings. No matter how good the shop is, inevitably you will find sloughed skins, feces and other dirty materials in the cage. However, look at the consistency of your findings and excessively dirty surroundings. Overcrowding in tanks should be avoided, and if any dead animals are found in nearby enclosures, stay away from purchasing the animal. Make sure you are buying captive bred stock; wild caught snakes can harbour all sorts of problems and should be avoided by beginners.