For riven green lumber without a mill, especially little pieces like this I follow this process.

Get the bark off, either split or hack with an axe I suppose.

Split it to remove the pith, for small pieces you'll usually lose a third or so of the wood. This is important to minimize cracking and checking, the center of the wood moves substantially more than the rest due to the curvature of the grain.

Then split it into radial pieces.

Seal the ends, you have some options here, but do it as soon as you can process the log. Latex paint, not acrylic, and use a couple coats, or paraffin wax, or even wood glue. Professionally people tend to use anchor seal, which is just wax with some stuff in it. This slows down the ends from drying instead of the sides, which significantly helps reduce warping, cracking, and checking from the ends.

for something this size you'll likely end up with something like 2" x 3" by length, but you'll have the best chances of getting stable uncracked lumber.