A small design system is a good place to start

Start with what repeats

Review three screens from your latest project. Look for repeated decisions: button heights, text sizes, corner radii, and the space between elements. A useful first system captures what the work already needs.

Name the decision

Give each repeated choice a purpose. A color called Action is easier to use than one called Pink 03. Keep the first set small enough that another designer can understand it in one sitting.

Test it in a real layout

Build a complete screen using the system. Where the rules fail, adjust them. Document useful exceptions, and resist adding a new component for every small difference.