Use a double boiler to melt your paraffin wax. If you don't have a double boiler put a pan half-filled with water to boil on the stove. Once it’s boiling, turn down the heat so it is only simmering and place a metal or heatproof glass bowl on the rim of the pan so that the base is only just touching the water.
This is an easy way of getting your candle wax melted without it getting too hot and burning off. Your wax will take a few minutes to melt and should be totally transparent once it has.
While you’re waiting for your wax to melt, you can wick your mold. Thread your wicking needle and push it through the hole of your mold. De-thread your needle and put it to one side, leaving just your wick threaded through the hole at the base of your mold. There should be enough length so that the wick extends beyond the open top of your mold a few inches (not the hole at the base).
Now you’ll want to make sure that no wax can escape out through the bottom of the mold.To do this, take some of your sealant (blue tack or preferably white tack can be used as a substitute) and plug the hole on the outside of the base of your mold. You can also wrap it around the wick so that it doesn’t move through the hole.
The mold can then be placed the right way up. The remaining of your wick then needs to be threaded through your wick holder or wrapped around a pencil that sits on top of the mold.Wicking your pillar mold correctly should make sure your wick is completely straight when you pour your wax.
By this point, your wax should be completely melted. Check the temperature with a temp gun or a thermometer. You want your wax to be relatively hot when you pour so that you get a nice glossy exterior of your candle. For paraffin wax, I recommend a pouring temperature of between 180-190F. Although not absolutely necessary, I find warming the mold before pouring also helps to get that smooth surface on a candle. You can do this by resting the mold on a radiator, or popping it into a warm (but not hot) oven for a couple of minutes.When it’s time to pour, make sure your wick holder/pencil stays in place and that you pour at a slow, steady pace. This will make sure your candle burns properly and that you don’t introduce any air bubbles into the wax as you pour. If you find that the wick holder is getting in the way while you're trying to pour the wax, move it off-center and then return it once you've finished pouring. Put your excess wax to one side, as we’ll be making use of that later on.
Keep an eye on it over the next few hours, waiting for it to begin to harden. This can take about 2 hours, but be sure not to let it completely cool. Once you’ve reached this stage, grab your skewer or bamboo stick and push vertically into your wax, leaving behind a hole that extends down leaving roughly an inch on the bottom of your mold. This sounds crazy, but you’ll want to do this a few times around your wick, but being careful not to disturb it. This should allow your wax to contract as it cools without creating horrible sinkholes, you can read more about avoiding sinkholes below.
Once your candle has cooled, top up with your excess wax, filling the holes you have made as you go. Your candle should then cool once more with a lovely flat surface on the bottom.[
Once your diy candle has cooled enough, gently work it out of the mold. If you’re struggling, pop it into the fridge for about 20 minutes, but with a metal mold you shouldn’t have too much difficulty getting it out. Once it’s out, trim your wick at both ends and it’ll be ready to burn! I recommend leaving them for a couple of days before you burn or gift them, but otherwise, you’re all finished.