Hi I’m new and I was wondering if I cast a candle spell am I supposed to wait till the candle blows out and then it would work

The common idea is that you should let the candle burn all the way and then your intent is released. But that doesn't have to be the case. If it's a long term thing you can snuff the flame out and then relight when you want to continue your working. Also I have had a spell show results before the candle was even halfway through (I still let it burn all the way)