Simple considerations or design decisions that apply to most game mechanics. Not every guideline will apply to your game, but those that do will benefit large numbers of gamers, and are easy to implement if thought about early enough.

If you’re looking for a few quick ideas of what to get started with, the four most commonly complained about accessibility issues (source) are remapping, text size, colorblindness, and subtitle presentation. If you can address those, you’ll make a significant difference to a large number of players.

Motor

(Control / mobility)

• Allow controls to be remapped / reconfigured
• Ensure that all areas of the user interface can be accessed using the same input method as the gameplay
• Include an option to adjust the sensitivity of controls
• Ensure controls are as simple as possible, or provide a simpler alternative
• Ensure interactive elements / virtual controls are large and well spaced, particularly on small or touch screens
• Include toggle/slider for any haptics

Cognitive

(Thought / memory / processing information)

• Allow the game to be started without the need to navigate through multiple levels of menus
• Use an easily readable default font size
• Use simple clear language
• Use simple clear text formatting
• Include interactive tutorials
• Allow players to progress through text prompts at their own pace
• Avoid flickering images and repetitive patterns

Vision

• Ensure no essential information is conveyed by a colour alone
• If the game uses field of view (3D engine only), set an appropriate default for expected viewing environment
• Avoid VR simulation sickness triggers
• Use an easily readable default font size
• Use simple clear text formatting
• Provide high contrast between text/UI and background
• Ensure interactive elements / virtual controls are large and well spaced, particularly on small or touch screens

Hearing

• Provide subtitles for all important speech
• Provide separate volume controls or mutes for effects, speech and background / music
• Ensure no essential information is conveyed by sounds alone
• If any subtitles / captions are used, present them in a clear, easy to read way
  

Speech

• Ensure that speech input is not required, and included only as a supplementary / alternative input method

General

• Offer a wide choice of difficulty levels
• Provide details of accessibility features on packaging and/or website
• Provide details of accessibility features in-game
• Ensure that all settings are saved/remembered
• Solicit accessibility feedback
  

* Sources of data on most commonly complained about issues are publicly through tracking of social media mentions, and privately through collation of input sent through publisher feedback routes. Most complained about is not necessarily the same as most needed, some players through impairment or stigma are less able to raise issues. But addressing the four most commonly complained about can provide a useful starting point.