Embarrassingly enough, it doesn't look like it's in our current in-game help, although we'll be looking to add that soon.
Quick crafting rundown: Unlock blueprints by progressing in the game, and collect the ingredients by doing outbreaks and bosses. Once you've collected the required ingredients (which you can see by clicking on the blueprints) you can drag the ingredients to the workbench, and click craft. Hope that helps!
 "MedievalShark"){kind=icon}
 "Dead End Defense"){kind=icon}
 "Zombie Slayer"){kind=icon}
 "Elona Shooter"){kind=icon}
 "Enigmata: Stellar War"){kind=icon}
 "Zombie Madness"){kind=icon}
 "Mud and Blood 2"){kind=icon}
 "Kingdom Rush"){kind=icon}
 "Age Of Wind 2"){kind=icon}
 "Realm of the Mad God"){kind=icon}
 "XenoSquad"){kind=icon}
 "Lucky Tower"){kind=icon}
 "Civilizations Wars"){kind=icon}
 "Bullseye (Interstellar Marines)"){kind=icon}
 "Burrito Bison"){kind=icon}
 "Rebuild"){kind=icon}
 "Caravaneer"){kind=icon}
 "A Bonte Escape"){kind=icon}
Embarrassingly enough, it doesn't look like it's in our current in-game help, although we'll be looking to add that soon. Quick crafting rundown: Unlock blueprints by progressing in the game, and collect the ingredients by doing outbreaks and bosses. Once you've collected the required ingredients (which you can see by clicking on the blueprints) you can drag the ingredients to the workbench, and click craft. Hope that helps!