You toss both the twine and the snake scale onto the ground, you chant a sacred ritual while holding the gemstone, and a smoke envelopes the twine and snake skin. The smoke dissipates very quickly, and where the twine and scale both were, is now a snake. It's stats are shown below.

The snake lasts for up to ten minutes (concentration), it is defeated, or until you dispel it. You can control this snake on your turn as a bonus action.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the amount of serpents summoned increases by 1d4 for each slot level above 3nd.