While I consider my ethical beliefs to have an egoist justification, I do not consider them “selfish”.
Selfishness, to me, means doing things without regard to others, to behave in an arrogant and atomistic manner. When someone tells you “don’t be selfish”, they don’t mean “don’t act motivated by what makes you yourself happy”. They mean not to ignore the opinions of others, to show them unkindness, to be uncooperative and self-absorbed.
From an egoist perspective, selfishness is not advisable. As I have stated earlier, egoism done right is social. Egoist motivations done right lead one to stereotypically “altruistic” places – cooperation, love, revolution. There’s a reason why anarchists often admire Stirner – because a world based on his ideas, if you really stop and think, will be significantly closer to Kropotkin than Rand.