Start with

• Modern Macros video
• Racket Guide:Macros or Fear of Macros
• Beautiful Racket:Macros
• https://school.racket-lang.org/2019/plan/

Racket includes additional support for macro development: A macro debugger to make it easier for experienced programmers to debug their macros and for novices to study their behavior, and of macros. And the syntax/parse library for writing macros and specifying syntax that automatically validates macro uses and reports syntax errors.

Follow with Introduction to syntax/parse

This is supported by a collection of examples Syntax Parse examples.

• Mythical Macros
• Macros and Languages in Racket

Syntax parse examples includes links to tutorials

https://docs.racket-lang.org/syntax-parse-example/index.html

the ones from Racket summer schools are pretty good IMO.

https://summer-school.racket-lang.org/2018/plan/mon-mor-lab.html

The corresponding lecture note is at https://summer-school.racket-lang.org/2018/plan/mon-mor-lecture.html

The full schedule is at https://summer-school.racket-lang.org/2018/plan/index.html