1.vigorous exercise an absolute must if you are planning to dance. maybe plan for a month of exercise for every 30 seconds you are going to dance. hence a 3 minute song would require 6 months of rigorous exercise in advance.
2.not lip synching would be great.
3.looking like you want to do what you are doing is also helpful.
Just a few thoughts.
PS : Perhaps a viewing of Khabi Khushi Khabi Gham would help? They dance a lot in that.