How polite to be

I'm going to Japan on holiday next year (woo!), and I was wondering how polite I should be when speaking to staff, such as hotel staff and train-station staff. I don't want to seem awkward because I'm speaking too politely, but I don't want to be rude either! Thanks in advance for any help :)

Probably just normal politeness would be fine, ie. -masu endings, but not plain forms of verbs nor keigo. Though, I haven't used anything but plain Japanese for a while now...

Thank you! I was hoping you'd say that really, haha :)

The language on this website is seen by many of them as too polite and if you make friends with Japanese they will tell you and try to teach you more casual language.