Save heavy cardboard type containers. Useful types of cardboard include a Pringles can, Chinese take-out containers, or waxed milk cartons. Make sure that the cardboard is coated with wax in some way... regular cardboard will absorb the melted wax and become a fire hazard, not to mention a mess.
Wipe the inside of the container with a damp paper towel to remove any food residue.
Attach your wick to the center of the inside of the container. You can use a little scotch tape to do this. Also a good way to attach the wick is to melt a space for it when the candle is done and put the wick in.
Lay a pencil (or similar object) across the top of the container and tape your wick to it, so that the wick is centered in the container.
Pour a little bit of melted wax in the container and wait a few seconds to make sure the container isn't going to leak.
Pour the wax into the container almost to the top. Reserve a little wax for topping up, as the wax shrinks into the center as it cools.
Wait several hours or overnight for the wax to cool and harden.
Let the candle cool. When the candle is cool, peel the container away.
Bits of Crayola crayons can be added to the melting wax for color.
You can also use a muffin tray for a mold. Once the wax has set and cooled, bang the tray upside-down on a counter to get the cute little candles out.
You can also use frozen juice cans (the cardboard type) as a mold,as well as oatmeal boxes, card board egg containers-please do not use the styrafoam type. You can also use the larger tomato cans for a large pillar and you can use a spray type of oil i.e: Pam to use as a release for your molds if you don't want to pay for 'mold release'.
Place plenty of newspaper under your project in case of spilled wax. And be careful because melted wax can burn your skin.
Using crayons to color your candle may cause your wick to plug and the result will be a candle that does not burn properly and could even cause a fire. There are many good Internet sites where you can buy candle wax, candle coloring and other additives to increase the chances of making an attractive and safe candle.
Paraffin as well as soy and other waxes are very flammable. Never melt any wax directly over fire or heat. Always use a double boiler. A coffee can set in a pan water that is on the heat will work in a pinch but it is much safer to use one pan with a handle set in a pan of water.