Pull nails. Cut cross boards from inner boards. Retain two pieces for arms.
Cut legs, leaving on leg long enough to attach back. Leave another long enough to attach arm rests.
Add boards to stiffen seat and back. Cut holes for eyes and nostrils. Cut teeth.
Enjoy your chair.
See how they are cut with a curve? Slice some in half for the seat. Use two for arm rests.
The pallet flat boards are cut from seat to top of back, leaving the middle three longer for the skull teeth