To get the log cabin effect, one side needs to be darker fabrics and the other side lighter fabrics. Using brown, a darker teal and the light blue would be gorgeous. Maybe you can use this Google link to find one you really like. It's a great pattern for beginners too. It will take multiple fabrics in the color way you decide to use. Something bright for the center beginning square like a red or orange.
https://www.google.com/#gs_rn=21&gs_...w=1366&bih=658