Creating your own sigil for your magical purposes us a great way to focus your intentions, highly recommended for beginners or advanced magicians.
After the sigil charging process is done, your desire will then be sent into the universe by various methods like burning or burying it.
What I have done is fold the sigil into a square and place it in my book of shadows until my goal has been reached, once I have achieved success I will then burn the sigil as a sign of completion of my ritual and the task of the sigil.
If the sigil is made to function as a talisman or if it represents a deity, then it is often activated over and over and should not be destroyed.