Nothing to worry about. It'll be a breeze. Jordan's easygoing.
Only thing to bear in mind is to dress more conservatively than you would at home. Don't know if you're male or female, but leave vest-tops and tight clingy clothing (Lycra etc) at home: you should be covering your shoulders and upper arms at least (and females should be covering the chest: round-neck or V-neck T-shirts are fine, but nothing that plunges or shows cleavage...). Long shorts (knee-level) are ok on men, but if you want to show respect to local people and their culture, wear proper long trousers (i.e. not loose beach-style brightly patterned ones). Wear a T-shirt if you like, but a button-up shirt broadcasts a sounder message about the kind of person you are and the kind of value you place on cultural sensitivity. If females want to show respect and be given respect in return, they should not wear shorts or T-shirts.
(You'll see plenty of tourists in Jordan doing the opposite to all the above - loads of men (and women) in shorts, loads of clingy Lycra, loads of beachwear - and nothing happens to these people - they have a great time, and probably get on fine with people they talk to. But they're still being insensitive, immodest, crass and ignorant - it's just that Arabs will not be so rude in return as to point it out. They will smile and say welcome to Jordan, and then just charge them double, or mutter something in Arabic to their buddies...)
Best of all, learn a few phrases of Arabic, so you can say something friendly. 'As-salaam walaykoom' (hello), 'shukran' (thank you), 'keef halak' (how are you? - just a general friendly way to say hello) - and when people say 'Welcome to Jordan' or 'Ahlan wa-sahlan' (welcome) you can say 'Ahlan beek' back to them (or shukran). Smiling and talking Arabic shows that you respect their culture and are doing your best to be a decent visitor to their country.
Don't worry about taboos - the main thing is not to look outrageous by revealing your body or dressing lazily (people really care what they look like: stuff that's torn, holey or dirty is out) and to act in a respectful way to people by smiling, talking a bit of Arabic and taking more time to interact than you would at home. Those are the two things that anger people most of all about foreign tourists - immodest dress and verbal rudeness.
Thanks for asking. Have a great trip.