An except from my level design notes from Camera Anima. When I started, I was familiar with Ren'Py's general programming but not how to take advantage of the engine to create point-and-click gameplay or item use. My design notes were intended to be an outline for the components of the game I knew were the bare minimum to complete the demo and stetch goals for components I wanted to introduce but was unsure I'd be capable of.
Introduce primary characters, setting, and overall plot and conflict.
Introduce player to navigating through choice menus.
Introduce player to cutscenes and general point-and-click exploration (should be able to click on some points to get a response).
An area for minor exploration/point-and-click interaction and a second area to transverse to.
At least one narrative choice menu navigation
Two cutscenes. One to at the start and one that makes up the bulk of the scene for exposition and character interaction.
Character art for the cutscenes (3-4 poses per character).
Optional scenes or dialogues.
A third area to explore.
Additional art for objects and newspaper.
Intro cutscene->minor exploration level->exit area to change level and view new cutscene->narrative menu choices->cutscene->end story mode.
Should present the player with at least one problem (need to enter locked building) and a solution.
Dialogue should provide hints for player action, both for avoiding bad endings and for knowing where to use or find objects.
Objects need their own art and should appear and disappear from the level with appropriate flags.
Introduce the player to picking up and using objects.
Be played and relatively understood without playing the story mode.
At least one object needed to complete the level.
Two or three areas to explore.
One introductory cutscene to provide context and inform the player of the goal.
Problem and solution should be solvable within 5-10 minutes.
Bad ending for using an object at the wrong place.
An extra problem to solve or object needed to complete level.
Alternative means of completing the level.
An inventory that displays items and a description when the player clicks on the individual items.
Intro cutscene->Introduction to problem->Exploration through areas->Collection of necessary objects->Use objects at correct points->Exit area to complete exploration mode.