How do you prep pallets for DIY pallet furniture safely?

[Noah_H]

I found some free pallets and want to try making DIY pallet furniture, but I've heard they can be treated with chemicals. How do I properly clean and prepare pallets for indoor use? What tools do I need for basic DIY pallet furniture projects? I'm thinking of starting with a simple coffee table or bookshelf. Any tips for someone new to working with pallets?