First of all, relax. The snake has only been in your care for 1 day. I wouldn't even offer it food for a few more days at least.
Secondly, there are around 10 species of sandboa and a dozen or so "morphs" of some species. Which species you have can determine what strategy to use. Yours is probably an East African/Kenyan sandboa, but if it is not, you should tell us first. Getting a young kenyan to eat is a slight different issue thatn a young conicus or miliaris.
There are a few tips on this page - www.kingsnake.com/sandboa/feeding.html - that might help.
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Chris Harrison
San Antonio, Texas

