Often when making things out of pallets, separating the slats from the pallet beams takes time, and the wood has nail holes (You can read this article for tips on how to dismantle a wooden pallet). Here is a pallet wood planter that was to be a mold for a cement pot, but the effect looks good anyway.
The pallet is sawn along each beam, so the wood comes to the same length, with no nail holes. The slats were wrapped in a shingling mode around a bucket, with a length of irrigation hose joined together to hold the slats in place while wood screws are screwed in. The top slats can splay out a little to avoid a straight up and down effect.