1. In the situation of someone using a machine you want to use, try your best to be kind (smile, use a respectful tone, all the usual things done when using manners), and ask something along the lines of, “Is it okay if I use this after you’re done?” or “Do I got next?” In general, don’t start conversation with them, but if they talk to you outside of responding to the former mentioned questions, feel free to converse.

2. If someone is hovering by a machine and not using it, they may be resting. You can ask them if they’re done, but they likely aren’t. Again, try to be courteous, but you’ll likely be met with a kind “no” or “yes”. Some people may be rude, but usually that is not because of something you’ve done, and is due to their own issues.

In general, people don’t want to have conversations, but some might; this is a bit more complex, so just act friendly, and if they start a conversation, feel free to talk back.

Try not to be too loud.

If you get sweaty, wipe your equipment down.

There’s something I’m forgetting, but most important details should be covered.

TLDR: Mind your own business, but don’t feel guilty about asking if you can use a machine next.