Been studying the soap recipient and decided to go for a wooden look (even if I had second thoughts to go for a metal one as  written in the sketch). The problem meanwhile is how to strap it to the hippo, so after some browsing for horses saddles images and sketching i came up with this:

Next the saddle will have to gain more shape, need to add leather strips , seat , buckles and so forth , before i can start texturing. (the chicken is only to give it a sense of  wrong scale.