How do you clean your physical game controller?

Yep. Isopropyl alcohol, sparingly (don't need a lot) on a cotton swab works well. Not enough to leave moisture though so it won't hurt anything.

I use a twist tie to clean the gunk out of the side cracks.

I've found though that goo-gone works better than alcohol but you'll have to buy that. Alcohol works in a pinch.

I would use a damp wrung-out rag with just a tiny bit of soap in it too wipe it down. I might come back with clean water, still wrung-out.

Wooden toothpicks are great for the cracks because they are softer than the plastic.

I would save the IPA on a swab for any electric contacts, assuming you have removed batteries. If you can't remove the batteries, I would wait until you are having physical connection issues or have spilled something on it.

Step one is prevention. Wash my hands before playing. No eating with cheeto fingers, &c. To clean, I use diluted dish soap on a rag. Very wrung out so there's no chance of getting the internals wet. Wipe it on, let it sit for a couple seconds, wipe it off with a different damp cloth. Use clean, damp cloths until all the soapy shit is off (part of the reason I dilute it). If there's something sticky, like say that sticker on the back of the ps4 controller has fallen off, I've got adhesive remover (I have Rx strength stuff I use but orange oil is great, same method) before I go over it with the previous process. Rarely need to use the alcohol wipes but each controller gets that a few times a year.

Tldr, usually alcohol is the gold standard of cleaning electronics, but soap removes the oils that come offa my hands better. I just do it carefully. Ymmv.

Eyeglass cleaner with coffee filters or get the packets. Or 3 parts alcohol to 1 part water with an optional drop of dish detergent.

This is the best option for phone screens too. My phone is 5 years old and the coating on it is still good.

Windex, paper towels, q-tips, toothpicks.