Fundraising practices is an archives tag for lorenweisman.com and looks into the way non profits operate with honor and authority.
See if they have information on a board, look for social media sites and if it is a new charity after some kind of event, look to see if it is tied to an established non profit that has been around for a while.
Making the donation on a secure site also helps and be very careful about crowdfunding sites as many problems have been reported after major events about people taking the money… and running.
Vet the charities for fools just like you should vet the marketing fools to avoid being fooled.
As you vet, it is not about finding a charity that gives 100%. They are few and far between. Any charity will need operational flow and they do report it. I prefer charities that have operational costs of at most 35% and down. Those that have higher budgets seem a little suspect to me.