I have been self-studying trig using (first) the Khan Academy [trig course](https://www.khanacademy.org/math/trigonometry). Here is a path through it if you want to revise and/or study yourself.
1. [[Basic Trigonometric Functions]]
2. [[Inverse Trigonometric Functions]]
3. [[Trig Ratios of Special Triangles]]
4. [[Trigonometric Functions of Complementary Angles]]
5. [[Pythagorean Trigonometric Identities]]
6. [[Unit Circle Definitions of Trigonometric Functions]]
7. [[Radians]]
8. [[Geometric Construction of Trigonometric Identities from the Unit Circle]]
9. [[Trigonometric Identities from Rotation]]
10. [[Sinusoidal Functions and their Graphs]]
[[Trigonometry Rote Learning]] is a cheat sheet I'm putting together for things I just want to learn to save myself some time. I've been using ankiweb for this and will link my deck when I feel it's in a good place.
## Books
1. "[Trigonometry Essentials Practise Workbook with Answers](https://www.amazon.co.uk/Trigonometry-Essentials-Practice-Workbook-Answers/dp/1477497781/ref=sr_1_1?crid=ZTBU0GGQDBPE&keywords=trigonometry+essentials+practice+workbook+with+answers&qid=1695188813&sprefix=trigonometry+e%2Caps%2C82&sr=8-1)" by Chris McMullen. This is helpful for giving tons of practise exercises to just get used to each of the concepts. It tackles things in a different order from above.