This may or may not be as helpful, but the biggest thing I have done that’s helped over time and a lot of repetition is reminding myself what I can and can’t control - the things I can’t; I just have to remember that it’s okay if it doesn’t work out, there are other options. The things I can - I just have to do my best and go from there.

I've had GAD for 14 years and the overthinking is awful. Something that helps me is finding a distraction, anything that will distract your mind. I'll play my favorite game on my phone, usually something relaxing like a coloring game, or sometimes ill listen to nature sounds. Taking a walk helps calm my mind slightly as well. If I'm having a panic attack ill tell myself that this has happened before and it will be ok. Ive felt these things before but it will pass. I hope this helps.

I totally agree with distraction! That's helped me a lot, another great thing to practice is reality checking too. Trying to take a step back and think about a situation objectively and list the facts you know to help you focus your thinking.

I play puzzle games on my phone a lot! Listening to podcasts also helps me if I'm doing a mindless task or drawing.