If you are using Gnome stay with that first. You can try gnome extensions and gtk themes, there are lots of possibilities. Many of the things that people post for other window managers will not work on Gnome.

Then know your command line well https://github.com/jlevy/the-art-of-command-line

Then try to automate things, such that e.g. you can open a QR code of your clipboard with a key binding. Or whatever cool things you want your computer to do.

If you like these things and you have a lot of time, try other window managers as well. Start with something that has a good example config and good resources online, I believe sway was pretty easy to get into for me.