Hey, you can just say no to an invitation to a dance. “No thank you, but thanks for asking,” is a nice response. You don’t need to give anyone a reason or excuse. Sometimes a lindy hopper just don’t want to dance.
You can also be ok with someone saying “No thank you,” to your dance invite. Just smile and say “No wuckers,” then find someone else to dance with. If you get a couple of knock-backs in a row maybe check people’s body language before you ask?
Also: sometimes people just don’t want to dance with you. Be ok with that. If you practice being ok with that, you’re actively undoing the bullshit power dynamics that make women feel they have to dance with rough, creepy, or just plain nasty people. You’re being totally awesome.