A big help would be if all the celebs stopped flying around in private jets but I'm confidant that they want all "the little people" to save the planet while they continue to do what they do.
They need to fly on private jets so they can warn the people all over the World! If they burn a ton in order to convince somebody else to save a ton, it all comes out in the wash... see!?!
The crucial point is - it would make literally no difference to our climate if everyone on the planet flew around in a private jet. Anthropogenic CO2 is a truly tiny part of climate change (its 0.28% of all greenhouse gases, and greenhouse is a small peturber compared with the milankovitch cycle and solar changes). Also CO2 is buffered by plant uptake and ocean absorbtion.