A soft brush, the longer the bristles the better. I use one by Befaco but I think that’s a European brand.
Something like this seems ideal to me: https://www.amazon.com/Keyboard-Cleaning-Wooden-Anti-Static-Cleaner/dp/B09YCF4ZHQ/ref=mp_s_a_1_6?crid=7UL7IU2D4706&keywords=synth+duster&qid=1688285126&sprefix=synth+duster%2Caps%2C210&sr=8-6