There are a number of different types of colorants you can use. Results also depend on whether you are doing CP, rebatching or M&P. Since your scent oil is $$, it would be a good idea to do a small test batch using the colorant to actually see what the color will ultimately end up being in your recipe. Trust me, it does not always turn out like you expected.
And take notes as to amounts added for the test batch.
This link gives you a good run down on types of colorants.
http://www.teachsoap.com/colorants.html This is just an excellent site all around.
Here, she shows you results of using clays and natural colorants.
http://crafty.dyskolus.com/coloring/redpinks.html
I made a soap with rose scent that I called "Mama's Roses" for a very special person - mama. To get the dusky rose ccoloring I wanted, clay worked beautifully.
An idea I saw somewhere that worked well for me was to sprinkle crushed dried rose petals on top right after pouring. One drawback, while it does look pretty, it is a good idea to pick them off before using in the bath/shower. They stick everywhere.
For a different look, you could also use a pink/red/coral jojoba beads. Then simply swirl these mixed in white to your white base.
Digit
