Try a soft clean paintbrush (or even a CLEAN makeup brush if you have one). A slightly more stuff brush like a synthetic artist’s paintbrush can be used in stubborn crevices.
If that does not help, you can try pressurized air, such as canned air dusters or if you happen to have a compressor, you can try that (just use a lower PSI to be safe).
Gentle wiping with a non-abrasive cloth can work too!
If it is too dirty for these things to work, let us know. Maybe someone can think of something better.
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