Liquid colours, conveniently packed with a glass dropper to easily dispense the colour.The liquid colours are highly concentrated used at the rate of only .001 - .1% by volume to wax.
So if you want to colour 1kg use half a ml - converts to 10 drops for a medium shade and 20 drops for a bold colour.
As always this depends on your own taste. Pastels use only 1-2 drops per kg wax.
Any colour you add will be affected by the opacity of the wax, its whiteness. Soy is harder to colour and is generally sold in soft shades whereas the more translucent paraffin shows off its striking colour boldly and without shame!
For bolder colour, try Fusion wax.