Harvest beaver dams
Craft it in a Mortar and Pestle or Chemistry Bench using Chitin or Keratin and Stone
Tame a Beelzebufo and kill insects to produce Cementing Paste
Use a Megachelon to collect organic resources that can help support paste production
Use Achatina to produce Achatina Paste, which can replace Cementing Paste in some recipes
Loot it from certain caves, beaver dams, and supply drops
Use a Chainsaw or pick to gather Chitin and Keratin for crafting
Use a Doedicurus or other stone-gathering method to collect Stone for crafting
Farm insects in swamp or cave areas with a Beelzebufo for efficient paste farming