Here we have a clip of a YouTuber showing how they dress or prepare 7 day candle. For information on how I fix them, click on the link below.
The only think I would clarify on is that I would not personally recommend loading a petition paper into the candle as in the above video. I have done that once and only once and the result was being awoken at 4:00 AM to the smoke alarm going off and a house filled with black smoke. When the flame reaches the petition paper it will burn and it won't just burn up and disappear. Instead, it will burn like a wick and will draw up melted wax and produce a huge quantity of black smoke. So avoid loading petition papers into candles. Instead, place the petition paper under the candle or else tape it to the glass, or better yet, write it on a sticky pad and then just slap the petition paper on the side of the glass. If you are using the type of candles with a silkscreen or printed imagery and words, then a petition paper is usually not necessary. In those case what you can do is to load the candle with a snip of hair. As the candle burn the hair will cling to the side of the glass and everything should fine.
Once again, follow safe candle burning guidelines. Never leave a candle burning unattended.