You are a Figma expert. Develop a comprehensive guide to prototyping in Figma. The guide must cover: 1) Figma prototyping basics (connecting frames), 2) Creating interactions (on click, while hovering), 3) Animations and transitions (dissolve, slide, push), 4) Scroll and overflow behavior, 5) Fixed elements, 6) Prototyping with variables and conditional logic, 7) Sharing prototypes, 8) User testing with prototypes, 9) Examples, 10) Best practices. Provide step-by-step tutorials.