One of my happiest memories from my childhood was making a basic candle using materials I found lying around.
Making scented candles isn’t hard either. While you may find inexpensive candles at discount stores, thrifts, etc., you can often make them even cheaper. Besides the good price, you can pick the specific scent (and the amount) you want.
You’ll need a few pounds of paraffin or unscented soy-based wax, a small vial of scent formulated for candles, a length of braided wick rope, and a few wick tabs. You will also need a container of appropriate volume. It is important that the container becomes gradually larger towards the open end, and has no obstructions to prevent the candle from being removed. Glass would be a good choice, possibly metal if it has a smooth finish. You should find most or all of this at either a craft store or a hardware store. A greater variety might be found online. I would strongly recommend sticking with scents made especially for candles rather than experimenting with essential oils or other concentrated scents (unless you are following an established recipe). Some concentrated scents could cause breathing difficulties in close quarters.
Now that you have all of the materials, cut the wick rope to length. This length should be the distance from the bottom of the container (or mold) to the opening, plus roughly eight inches. Next, place one end of the rope through the hole in the wick tab base and crimp the metal securely with needle-nosed pliers.
A double boiler is strongly recommended for melting the wax. Hot liquid wax is highly flammable, and any spill onto the heat source is a fire hazard). The wax should be heated to 180º F. A cooking or candy thermometer may be useful. Stir the wax gently as it heats. When it reaches 180º F, and all the wax has melted, remove it from the heat.
Bearing in mind that the wax needs to be poured into the mold at 125º F, you should add the scent (and any optional coloring) and mix at an intermediate temperature. Let it cool substantially so the scent won’t dissipate before the wax solidifies, but enough above 125º that the wax doesn’t start to congeal (or harden) before it is poured.
After carefully pouring the wax into the mold, let it cool for several seconds to a few minutes, depending on the candle’s size. When you see the wax begin to congeal at the edges, drop the tab end of the wick into the candle as near the center as possible. You may need to use a wooden food skewer or some other stiff, narrow item to push the it to the bottom. Put the upper end of the wick over a ruler placed across the open top of the mold, so it will not fall into the wax.
Let the wax harden for a few hours or more. It should be easy to remove from the mold. Finally, simply trim the wick.