How do I introduce small corn snakes to aan adult corn snake

If we're talking snake etiquitte, I'd introduce them the same way you'd introduce your little brother to an adult but with snakes, I'd do it through the glass of separate cages. Snakes are sometimes canibalistic and the bite-size little ones may never make it to adulthood in the same cage with an adult.

Manners are really important so do the following

Mr. or MS. Corn Snake, I would like to introduce myself, I am a junior Corn Snake. and would love the opportunity to join your abode.
Thank you

you'll be feeding the small snakes to the big one. snakes as a rule should never be kept in the same cage, unless they're over similar size AND well fed.