To be sure my designs are accessible, I respect these visual guidelines :

• apply readable sizes to texts
• define and apply solid information hierarchy
• use sufficient contrast ratio with colors
• always diplsay dataviz labels

To respect this checklist needs a well-built design system. I was personally involved in several design systems production and maintenance, and I like to have an open line with design systems teams in case some thing needs to be discussed. 

Some accessibility requirements go beyond visual guidelines, they are behavioral :

• don't rely on hover to display important informations
• always display buttons labels, no lone icons (except rare and specific situations)
• respect minimum size for interactive components
• provide alt text descriptions for icons and images