If you're using this recipe as a base for a soap you're adding your own colours and fragrances to, take a note that in your early attempts at natural soap-making it is far easier to fragrance a soap using pure essential oils. Avoid most fragrance oils as they are almost all alcohol based (something like dipropylene glycol) and virtually all forms of alcohol can cause 'siezing' in a soap mixture. This is when the mixture starts to set solid very rapidly, before you have a chance to pour it, ruining all your efforts. Also, bear in mind that many 'pretty' additions to a soap such as dried flower heads etc. will very possibly turn brown and discolour the soap if added to the mixture whilst it is a liquid. This is because of the high water content and caustic nature at that stage. Additions that work well are dried pulses, spices and dried herbs. Some spices achieve good colour as well. Turmeric (yellow) and paprika (salmon-like) are two examples. Petals etc. (like dried lavender) can be successfully 'pressed' onto the surface of the soap after pouring, before covering and insulating, although keep your gloves on when doing this as the mixture is still caustic at that stage. Generally food-safe colours are not suitable for natural soap-making (there are some exceptions). There are colours that work well and are simple to use (see tip above). Procedure as follows...
All ultramarines and oxides require mixing with a little water and can be added at any stage after all ingredients are in the soapmaking pan together, up to the trace.
Some types of pigments (known as insoluble pigments) are NOT water soluble and give colour to soaps best in warm oils. Add the powder or dispersion to melted coconut/palm oil and whisk in very thoroughly to avoid any 'spotting'.
Ground Spices are basically in 2 varieties. Those that will add colour to the oils (Turmeric and Paprika) which can be added to the warm oils similar to Lakes and those that simply add colour by suspension (i.e. gound cinnamon) which are best added near the trace in a little olive oil as a runny paste.
With ALL colours/pigments, the depth of colour will vary with the amount added. Keep colours subtle to avoid bleeding of colour into the lather when using the soaps. Mix up enough in a little water (except insoluble pigments) and add a bit at a time until the depth of colour you want is apparent. Guide for this size recipe... All ultramarines/oxides max 1 tsp (5ml). Most food-safe water soluble powders max 1/4 tsp (1.25ml). Lakes max 1/4 tsp (1.25ml). These are a guide only.
If you want to enrich your soap with specific oils for their properties (maybe hempseed or wheatgerm etc.) use aprox 1 Tbsb (15ml) at trace. Honey, also aprox 1 Tbsb (15ml) at trace. Exfolients, i.e. oatmeal or similar, up to 1/4 cup (60ml). at or before trace. Take care to ensure your soap is thick enough to 'support' any exfolient additions before pouring or they may sink or float (depends what they are).GUIDE TO SAP VALUES