A Continuous Spell can be activated during your turn in an open game state, usually in your Main Phase, unless a card effect says otherwise. It can’t be activated like a trap in response to something; once activated, it stays on the field and its continuous effect applies while face-up.

Simple rule

  • You activate the card during your turn.
  • It goes face-up in the Spell & Trap Zone.
  • Its effect then remains active as long as it stays on the field.

What you can’t do

  • You can’t activate a Continuous Spell during your opponent’s turn just because you want to.
  • You also can’t “chain” it the way you would with a Quick-Play Spell or Trap, because it is Spell Speed 1 when activated.

Example

If you draw a Continuous Spell on your turn, you can usually set it and activate it later that same turn, as long as no rule like Anti-Spell Fragrance is preventing that.

Extra note

If the card has a separate activated effect written on it after it’s already face-up, that effect may have its own timing rules. The card’s continuous effect and its activated effect are not always the same thing.

TL;DR: You play a Continuous Spell during your turn , in an open game state, usually in the Main Phase , and it stays on the field after activation.