Sepia colouring with Promarkers

I am quite new to Promarkers and this is my first attempt at a sepia image.  The stamp is a Holly Hobbie character I got free with the Card Making & Papercraft magazine. Its not great and I'm more than happy if anyone wants to leave some pointers in the comments.

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I used the Flexmarker Skin Tones Set 1 and the Coral Promarker.  I did struggle using the Skin Tones as they are all so pale I found it difficult to get any shading, hence using the Coral Promarker as well.  Although I'm not sure the Coral worked particularly well.  

I will keep on trying!