There are some fundamental issues with atheism ... not lest the various forms listed ... almost as many as there are religions.
The only way to promote atheism is to chip away at the fundamentals of religious belief

1. the bible is a collection of books written by men and the collection was chosen by a pope .... so publish the various texts of the books left out at the time ... the dead sea scrolls ... and all the contradictory texts.
2. make it clear that women played a massive role in the foundation of christianity ... there is plenty of evidence
3. promote ethics and morality, the basis of a society, as independent of any religion.

or, as I do, accept that most people are sheep and leave them to wander through their life secure in their contentment and expectation of something better when they die

You're talking about branding rational thought? Exactly who are you trying to sell it to? How does it matter what religious zealots think of those not stupid enough to buy into their bullshit? Why this need to label everything?

Can i donate money to this, and then claim ive never heard of you people, kinda like how Trump secretly supports Biden?

Humanist is a softer more palatable term for most people. Atheist has a more negative connotation and I reserve that for people who know me and won't change their opinion.

I’m not too concerned with the branding. A good logo would be good I suppose.

Not for me, too introspective

I have come up with a new (for me) label as it were since this site seems obsessed with them.  Functional Atheist.  Someone who's belief in "God" and all that may or may not entail is what it is but matters little in relation to his or hers interactions with others or the world.  
I feel the biggest PR nightmare for this site is the arrogance inherent in projecting Atheism outward as a opposing force against ALL religion and spiritual thought.  Many agnostics who speak in terms of doubt or personal spiritual journeys are roundly mocked or attacked.  And many Atheists seem to take a elitist approach.  They ignore or dismiss spirituality and belief as a zero sum thing with no positive impact on humanity.  Many seem to hold personal grudges against religion and use that as a club to beat anyone who even hints at a positive spiritual or religiouse experience.  
Atheism as I see it has no real answer to fill the job that for thousands of years of human history has been provided first by Myth and story and then by religion and spirituality.  Instead beating the dead horse that is the question without a answer; is there some version of a "God" anywhere?  Its a tired debate.  And really is irrelevant to the actual war we should be fighting; the war against ignorance.  One can be rational yet find comfort in spirituality.  One can be rational yet horribly amoral and cruel without some kind of ethical foundation.  
What is the ethical foundation of Atheism?  Were does it go past the tired battle against an invisible, impossible sky god?  I like the Universal Declaration of Human Rights.  I think Atheism needs to evolve past its obsession with the Judeo/Christian God and establish its own ethical framework and use it to fight the negative results and practices of any belief system that causes harm.  A grander less cheeky version of Satanism.
Instead of saying your God is not real.  Why not this; irrelevant of your god's exsistence if your causing harm/spreading ignorance we will fight you for that.  And if your god tells you its cool your wrong and we will fight your wrongness.  If your god says something is and it provides tangible benefits and spreads knowledge and truth as a result then go ahead and let your freak flag fly!  If it provides motivation for good works great.  The same if your a rational asshole doing harm but being really good at it.  Harm is still harm.

That's not an easy question to answer. People have tried before (the word 'Bright' comes to mind if I remember one correctly). But of course people are wrapped up in their religions so they get defensive quickly.
It involves fine judgement to be positive without looking smug and arrogant.

I guess I'm glad I agree with so many comments below -- I don't care much what people think. I'll work against them if they try to impose their opinions on me and mine but that's as far as I'll take it.