The things you will need
Two bolts and nuts, each 6 mm diameter, with length 8 cm
cut the part you need for axe
Leave at least two holes, that will be used future,
to mount metal in the wood with bolts and nuts.
Give the shape to the wood,
Sand it down with thin sandpaper.
and get ready for next step
Make marks for holder bit holes and drill it
Screw bolts and nuts
Engrave something on the axe and you are good to go