Start with the essentials, not the entire type system
When you first adopt TypeScript, the sheer number of features can be overwhelming. You don't need to master every advanced type trick on day one. In my experience, a handful of features deliver 80% of the value and make your code safer and more readable immediately. Here are the ones I'd adopt first.
1. Explicit function return types
TypeScript can infer return types, but being explicit about them acts as documentation and catches mistakes early. If a function's logic changes and the return type shifts, the compiler will tell you instead of silently breaking callers.
function getUser(id: string): User {
